Lean Engineering and the myth of multitasking


Multitasking is a praised ability in a world needing constant adjustments. Critics challenge the ability of humans to multitask, while others still believe in and praise it.

I know for long time now that I am no good at multitasking and felt somewhat ungifted until the day I attended a training session in which an experiment settled the case.

Experimenting mono and multitasking performances

The experiment is made of a series of simple single tasks, each having an equal number of elementary operations, such as adding 1 to the previous number, list a series of odd or even numbers, write the letters of the alphabet, etc.

In order to compare the performance between mono and multitasking, the time to complete all task is measured as well as the number of errors.

The first test is done in mono tasking mode, which means the tester does all the basic operations of the task # 1 , then passes to the successive elementary operations of Task No. 2, and so on.
The stopwatch is stopped at the last step of the last task.

The second test is performed in multitasking mode: the timer is triggered then the candidate performs the first elementary operation of the task # 1 , then goes to the first elementary operation of the task # 2 and so on. The stopwatch is stopped at the last step of the last task.

Test results

Compared performances

 Time in
Total time
Total time
Task 1 16
Task 2
Task 3
Task 4

Besides, multitasking led to many errors even the operations were very simple, elementary.

Accepted disturbances

Accepted disturbances are commonplace in our work environment; interruption by unexpected arrival of a visitor, a conversation initiated by a colleague, request for a superior or question from a subordinate, the phone ringing , incoming e -mail , etc.

To add to these, many persons keep checking their smartphone for incoming tweets or e-mail, the sound signal, when activated, irresistibly attracts attention and distracts form probably more valuable occupation.

All these disturbances are derivatives mobilizing our attention and mental capacity. This constant zapping causes the same effects as those described in the experiment; loss of time, deterioration of quality and over consumption of our energy.

Lean Engineering

Striving for Leanness in engineering means striving for efficiency. Accepting being disturbed believing multitasking is an efficient approach to good work is nonsense. All these task switching are just like handoffs in a production line: waste.


To learn more about bad distracting habits, read “The Magic of Doing One Thing at a Time ” ( Harvard Business Review Blog ) post from Tony Schwartz

You may experiment by yourself online with a >simple game<

And watch this video


SMED explained while doing laundry – Part one

SMED is a systematic approach to quick changeovers in order to minimize machine downtime.

>Lisez-moi en français

To explain what SMED is good for to non-specialists discovering it, I use the laundry example.

Let’s imagine the mundane washing machine is a very precious resource and it should wash (add value) as much as possible in 24 hours a day.

The machine stops at the end of a washing cycle and there’s no choice but swapping washed laundry with a new batch to-be-washed laundry. This exchange is equivalent to production changeover. In order to minimize the washing machine stoppage, the laundry swap has to be as swift as possible.

But before designing a laundry cannon to shoot the clothes high velocity into machine’s drum, let us observe how a laundry swap is done (go see).

The usual changeover cycle

When the machine stops at the end of a cycle, the “operator” has to notice it and be ready for action. If the machine does not signal itself and/or the operator is not waiting for this moment, the reaction time until noticing and acting is wasted.

The first thing to do is to remove the washed laundry from the drum. This clean laundry should be protected against stains and put in a clean empty basket for example.

Ah! Empty basket? Where is the empty basket? The time searching for the empty basket with arms full of clean laundry is lost for washing as the machine sits idle waiting to be fed another batch.

When the clean laundry is eventually dropped into a clean empty basket, and assuming the “operator” does not waste additional washing machine time to further take care of clean laundry, he’ll has to come back to the machine to load it with the next batch of laundry to be washed.

At this point boys have to understand to their amazement that delicate, white, dark and light laundry have to be sorted and washed separately, except for those who like their white shirt turn light pink thanks their daughter/sister/wife’s blouse. Girls usually know this.

If the to-be-washed laundry was not sorted beforehand, the time to sort it lets the machine idle and wasting more time.

Finally, one part of the sorted laundry is thrown into the drum, a gesture that could have be done in a softer manner, as the violent acceleration of clothes does not compensate much of the time lost until that point.

The changeover is not finished as long as the machine is not restarted. And before restarting, it should be refilled with detergent.

Detergent? Where’s the detergent?

While searching for detergent, the machine… sits idle.

When detergent is filled and machine started, the changeover is done.

This imaginary scenario is not that uncommon in households nor is the equivalent not uncommon in factories.

Instead of washing machine we’ll find machine tools or any production or test equipment. Instead of laundry it’s raw material or parts and instead of detergent, operators may look for tools, templates, jigs, plans or whatever should be handy and is not.

In the next post of this series, we’ll see how the washing machine downtime can be drastically reduced!

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What is operational excellence?

Operational excellence (OE) is a competitive advantage: it translates to increased production flexibility, improved customer responsiveness, and cost minimization. (Deloitte)

Operational Excellence is a philosophy of leadership, teamwork and problem solving resulting in continuous improvement throughout the organization by focusing on the needs of the customer, empowering employees, and optimizing existing activities in the process.” (source: http://improveprocess.blogspot.fr/2009/08/what-is-operational-excellence.html)

Operational Excellence is when each and every employee can see the flow of value to the customer, and fix that flow when it breaks down. It’s that simple. What this means is that each employee knows that the product moves from process A to process B in a specific quantity, at a specific time, to a specific location; otherwise, something is wrong.
Additionally, when something does goes wrong (and it will), they know what to do to fix it, without seeing their supervisor, reporting to management, or having a meeting. This happens in the office as well, where employees can see the flow of a customer order through several business processes and fix that flow when it breaks down in the same manner“. http://www.industryweek.com/companies-amp-executives/operational-excellence-defined


Operational Excellence is a structured and systematic approach to strive for sustainable outstanding performance. Performance is to be understood in the broadest way and in the context of the purpose of the organization.

  • For a manufacturing company, performance means high productivity, high quality, low scrap and minimum wastes and tight control of operational expenses.
  • In services, Operational Excellence is fast and accurate response, swift and error-free handling of files, and a pleasant customer experience, e.g. not required to repeat same data over and again because of multiple internal handovers.
  • For a hospital, performance is about patient care and experience, effective treatment, seamless journey and so on.

Operational Excellence was/is sometimes referred to as “world class” or “best in class”.

Operational Excellence is built on continuous improvement, which uses many methods, tools and techniques. Among these, Theory of Constraints (ToC), Lean and Six Sigma are the most common, each having specificities but also sharing many common tools and complementary mindsets.


What is SMED?

SMED stands for Single Minute Exchange of Die, a systematic approach to changeover and setup time reduction.

SMED is an acronym that made its way into industrial lingo for decades now. Its origins is in japanese automotive industry of the 1950s when Toyota Production System pioneers led by legendary Shigeo Shingo observed operations on shop floor.

>Lisez-moi en français

Exchanging a die of a huge press took hours, letting the machine – a valuable resource – stopped and producing no added value. Diminishing the changeover time allowed to convert wasted time into value adding time.

After analyzing the changeover process, the thorough elimination or reduction of unnecessary tasks and better organization cut the duration of a changeover from hours to minutes.

“Single Minute”, till today misleading, does not mean in less than a minute, but in a time measured on a single digit, thus between 0 and 9 minutes, or put in the pioneers’ spirit in less than 10 minutes.

Classic Changeover

Most often, the changeover happens like the time chart below shows. It starts when the last part from actual production batch is finished and ends when the first part from new production batch is ready to be processed at normal pace.

Breakdown of changeover duration

Finishing actual batch Dismount tools Change tools Adjustments (machine stopped) Trials Process new batch

The machine is usually stopped and all changeover operations happen in sequence, while the machine is stopped. The machine will start again only after completion of adjustments and trials. Sometimes after quality check and when the appointed staff gives its ok.

Most often all these operations are done without any standard method nor procedures or checklists. This means the changeover sequence and its duration is related to individual know-how, skills and habits.

Teamwork, several operators sharing changeover operations in order to minimize the stop time is also seldom. As changeovers take time, cause productivity loss and carry costs, the temptation is to dilute them in changing less often by launching bigger batches. This leads to adopt so-called Economic Order Quantity to define the production batch sizes.

The EOQ policy ends up with higher inventories and lower agility, which are opposite of what is required in the new paradigm.

Four steps to SMED

The first obvious thing noticed by the engineers was that during changeovers and setup the machine was stopped, even for operations that were totaly independent of the machine itself, like preparing tools, dies or various supplies. This led to a first step of the SMED approach:

Discriminate operations that MUST be done while machine is stopped, called internal setup (IS), from those possibly done while machine runs, called external setup (ES), and useless operations. By hunting down all causes of time waste, the SMED team finally came up with a sequence of four steps to reduce changeovers:

  1. Suppress useless operations, convert IS operations into ES
  2. Simplify fittings and tightenings
  3. Work together!
  4. Suppress adjustments and trials

External setups

Quick wins are usually easy to grasp. Identify external setup tasks and treat them like that: do before the changeover, before stopping the machine for those necessary before changing over. Conversely wait until machine is restarted before doing all tasks that are external setups but can be done after changeover.

External setups prior to change are typically preparations of prerequisites:

  • tools, parts
  • instructions
  • lifting material
  • pre-assemblies

Besides, take opportunity to unify parts storage like boxes, crates, feeders in size and types.

External setups post change are typically recordings and tidying up:

  • files, notes, tags
  • tools, parts, leftovers

Internal setup tasks reduction

Some operations considered at first glance as “internal” can be converted into “external” with significant reduction of machine stoppage.

These operations can be: presets and pre heating (in external owen, with external connection…)

Once conversions done, simplify fittings and tightenings

When all operations that can be done without stopping the machine have been identified and converted, the next potential for setup time reduction lays in the reduction of the “internal” operations. Among them, fittings and tightenings are a major category. The target is to:

  • suppress fittings and tightenings partially or even totally
  • minimize “turning” movements: they request several grasp-release motions!
  • fit at once, in a single motion
  • use blocks, jigs, templates
  • standardize tools, types and size of screws, nuts…
  • go for ideal: use only one type of screwdriver or wrench, challenge to suppress all tools


Once the die, fixture or template for the new batch is set, it is usual to have several adjustments to go through.
These adjustments are also time-consuming and extending the duration of machine stoppage. Adjustments are to be considered as waste. Would the setting be done properly the adjustments wouldn’t be necessary.

  • set standard values
  • find out adjustment-less methods through physical means, like stoppers, guides, blocks…
  • design custom-made tools if necessary

Work together!

If a machine is critical (bottleneck), its stoppage is to be reduced to the very minimum. It is meaningful in such a case to have a team focused about that. This team is made of the operators and techies from the workcell or workshop that temporarily let their current task down to help to perform a quick changeover on the critical machine. This setup team would act like the racing pit team, each team mate being assigned a special operation he knows well and performs flawlessly in a very short time.


Trials are like adjustments, to be considered as waste. Everything should be organized and done to make it right first time, without any need for trials.

Related: SMED Explained while doing laundry

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Goal Tree – Stating the Critical Success Factors

A Goal Tree is the kind of simple looking yet tricky tool. almost every time I explain the Tree principle and structure, my audience reacts with more or less subtle signs of impatience or disappointment “is this all?”.

Assuming the Goal is properly stated, which is far from being a given,when it comes to define the Critical Success Factors (CSFs), it is my turn to get disappointed.

Goal Tree

Goal Tree

Critical Success Factors (CSFs) are top most objectives that must be achieved in order to have the Goal achieved.

CSFs like any other objectives has to be set in a SMART way, SMART being an intrinsic quality as well as an acronym for:

  • Specific
  • Measurable
  • Attainable
  • Realistic
  • Timely

A non-SMART CSF would be “reduce our costs”. This is wishful thinking at best. Specificity makes the difference between a wish and a goal, therefore the statement has to be clarified: what kind of costs are we talking about? Unit costs? Overhead expenses? Operational expenses? How much savings are we striving for? Who’s in charge? Is this everybody’s objective or only managers’?

How will this objective be Measured? According to budget? Relatively to turnover? What period? How can we make sure the efforts will pay off and that contributors are on track?

Is this objective Achievable? Objectives that seem too far away and out of reach are discouraging, while objectives too easy to achieve are not very motivating challenges neither. If the challenge does not seem achievable, it’s maybe necessary to break it down into less difficult sub-objectives.

Realistic objectives can be challenging but must remain attainable. For example they must be achievable with current technologies or knowledge.

Finally, objectives must be Timely framed. A goal without date for a completion, is not a goal, it’s a dream. Time frame is also useful to positively stress the organisation, to give a sense of urgency.

Yet I keep being surprised how fluffy objectives are set, CSFs are stated.
CSFs are Critical in essence, meaning that if not achieved, the Goal is not achieved.

Stating vague, fluffy CSFs will not engage people to contribute and are no effective guidelines to align contributions.

CSF definition are top management’s responsibility and the quality of their statement reflects the quality of their strategic planning.

No wonder so many “strategic projects” fail with so poorly stated objectives. It is like top management defining a Goal and let the shop floor staff take care about details, with no more directions than the sole vision statement.

More about >Goal Trees here<

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Goal Tree for personal Goal

Goal Tree is a great tool to describe everything necessary to achieve a goal, from topmost objectives called Critical Success Factors (CSFs) to the underlying Necessary Conditions (NCs). All elements of a Goal Tree are linked together by a logical necessary condition relationship (in order to have… we must…), which is a powerful filter to avoid pollution by unrelated topics.

Goal Tree

Goal Trees can be used to set personal goals, like for example to build one’s own career path.

The Goal would be stated in a way like “in five years from now, I will be…”

The personal goal could be to get promoted or hired to a top executive position with a peer-recognized expertise in a specific field or track record of achievements.

The following questions may serve to prompt and inspire your imagination:

  • What do I want to do?
  • What do I want to have?
  • Where do I want to go?
  • What do I want to learn?
  • Who do I want to spend my time with?
  • How much do I want to earn?
  • How much leisure time do I want to have?

Source: http://coachingpositiveperformance.com/goal-creation-5-helpful-rules/

A handful of Critical Sucess Factors (5 maximum is my advice) will describe the future state more specifically. One would probably be a strong marker of position, like title, status and/or salary, e.g. vice president in charge of… with a yearly income of…

Another CSF could describe the field of responsibility like “domestic”, “overseas”, “x million of sales turnover”, “n hundreds of staff”.

Critical Success Factors are critical because ALL CSFs must be achieved to consider the personal goal achieved.

Each CFS is linked to some Necessary Conditions, whose name remind that without these conditions achieved, the upper CSF is not granted. These first level NCs are themselves subordinate to some lower level NCs and so on.

The tree-like structure led to the tool’s name: Goal Tree.

A personal goal tree is a way to structure and focus on necessary achievements, competencies to acquire or strengthen.

It is a better way to ensure the ambition of a bright future to come true than the vague statement “one day I will…”
At least for all in need of concrete and specific intermediate objectives!

More about >Goal Trees here<

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Goal Tree chronicles – four hours to fill six boxes

This Goal Tree session started early afternoon with the company’s top chief officers. While I explained the Goal Tree principle I could notice the usual grins meaning “You’ll get your tree filled in ten minutes, we perfectly know where we want to go and what must be done to get there”.

Well, then tell me what your goal is!?

The CEO spoke up and stated it in a short sentence.

Sorry Sir, I replied, this Goal is not suitable. It is not compelling, not sexy. Who would want to follow you for achieving such a Goal?

…puzzled audience…

I explained further: short-term survival (what the proposed Goal actually meant) is frightening, not compelling. People will think the situation is worse than they thought and the executives are focusing only on short-term survival, which means they have their doubts about it.
If you truly believe in the company’s assets and your ability to lead it into a new bright future, tell it!

What followed was a two hours debate and trial to reformulate the initial Goal. During this exercise, I pointed out several points the CxO mentioned among themselves but did not embed into their vision statement.

Yes, but we know it, it’s implicit!
Sorry I am no good at decoding implicit and picking up the unspoken. You should assume that many of your employees and of your customers are like me, not able to understand the hidden indications.

I explained that this is a lack of clarity reservation. A transformation project as vital as the one the company is going to engage needs a Goal expressed with clarity, so that everybody understands it without additional explanations.

This is not about wordsmithing, simply about clarity.

Once a more compelling Goal was stated, the CEO acknowledged it was necessary to refine and restate the Goal and this exercise was an eye opener.
Two more hours were necessary to select five Critical Success Factors. Many attempts failed because of the usual mismatching between Necessary Conditions and Critical Success Factors (CSF).

The grins had long vanished, the audience was now frowning, deeply concentrating to express the CSFs as clearly as they did for the Goal. The execs understood how important it was to be specific before searching for the underlying Necessary Conditions, and how this would help future communication.

By the end of the afternoon we had one Goal and five CSF stated in satisfactory way.

What first looked as piece of cake took four hours to correctly fill six boxes.

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One more management lesson from candy crush

In a previous post I wrote about parallels between candy crush and management practices, meanwhile I took another lesson while struggling to crush virtual candies.

I was stuck in level 100 for a long time, long enough to feed me up and let me try to accumulate 2048 in a matrix, another addictive game you may know.

In candy crush level 100 lays a bomb that looked very much like a cartoon time bomb. I logically tried to wipe out this bomb before its time elapsed and… invariably failed to complete the level.

>lisez-moi en français

Some times because the bomb went off before I could neutralize it, sometimes because I used up so many moves to get rid of the bomb I had not enough left to eliminate the gelatin.

One day as I gave it a new try, I allowed myself more time to consider the candies’ arrangement and noticed the number on the bomb would not decrease if I didn’t move a candy.

So this is no time bomb but one triggered when the allowed movements were used up. The number on the bomb displayed the moves before explosion, not the remaining time!

From the beginning I played with a false assumption. I relied on my first belief and did not check my assumption.

I kept being fooled by appearances as the faster I moved the candies in my hurry to get rid of the bomb, the faster this one blew up.

Once I realized I could take time and smarter plan my moves, results improved!

The irony of this story is that I advice so many people to refrain from hurrying into action, check their assumptions and run experiments to solve problems and failed to do it in this simple case. Shame on me!

Me included, how many people rush to solutions believing they have sufficient understanding of the problem?

This wicked game taught me a vexing lesson, up to me not to repeat it!


Special notice to NSA and the like: there is no hidden message in this post, it’s just about candy crush saga

About the author

Downsides of kaizen events

In a previous post I explained what kaizen events are and ended it with some reservations. In this one I’ll explain why. I am no opponent to kaizen events, I simply point out the deviations I have witnessed.

>Lisez-moi en français

kaizen events are quick actions performed in a very limited time, limited perimeter and focused targets. To achieve it, the group has to comply with the standard format.

Participants are rushing from one assigned task to the next, like remote-controlled by the moderator. There is little time and opportunity for participants to really understand, reflect and learn.

Therefore Kaizen benefits to managers solving problems in their area and moderators or kaizen office members for new scores but seldom benefits participants nor even the company, in the long run.

Why company seldom benefits from kaizen events?

First because the kaizen event is no good learning organization, as participants do not develop their own abilities to see problems and improvement potentials, design and carry out experiments to solve issues.

Kaizen event-driven activities keep depending on few champions to lead them.

No planned session means no improvement. People are not trained to improve by themselves nor entitled to do it outside the events.

Kaizen activities in general are welcome in a slowdown to keep paid people busy, but when business returns to normal, kaizen returns to low priority. Continuous improvement is understood as periodic improvement and performance is leaping from one level to the next according to events.

Kaizen events are focused to local problems. These local problems may be solved locally at the expense of some other area or process.
They lead to local optimizations which in sum cannot be the optimum for the whole system/company.

Put differently, kaizen events serve cherry picking independent problem solving, not always aligned with the Goal or really contributing to the organization’s Purpose.

In “Toyota Kata”, Mike Rother explains: “improvement workshop does not require any particular managerial approach. (../..) This may explain some of the popularity of workshops“. Further: “Since the workshop team moves on or is disbanded after a workshop ends, we have to expect that entropy will naturally begin eroding the gains that have been made.

The fast pace of kaizen events is used to overcome resistance to change, yet systematically rushing to implement solutions is a mere top-down approach.

So-called participation is only about giving a hand, seldom the opportunity to truly participate, e.g. Express, analyze, understand, experiment, build, argue, buy-in, carry-out, and learn.

Some organization develop lean champions only and depend on them for any lean-kaizen activity. When those champions have enough experience and track record of achievements, they’ll sell themselves to another company, leaving the previous one without real legacy.

Who’s to blame then?

Related: What is Kaikaku?

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What is kaizen event?

You may know from a previous post that kaizen means continuous improvement. A kaizen event is a planned session for improvement on a limited perimeter, usually focused on a peculiar topic or issue and limited in time. A kaizen event lasts generally a week or less.

Shorter kaizen events are often called kaizen blitz, a reference to WWII blitzkrieg, or fast moving warfare. In German blitz means lightning.

The session is formatted, phased. Participants go through the exercise with scheduled duties like gathering data, draw a situation map, analyze the problem, design a solution, try and adjust and prepare and present the conclusion.

>Lisez-moi en français

Most of kaizen events’ objectives is solving a given problem. The company’s kaizen office or the like generally has a list of improvement potentials and/ or problems to solve or a kaizen event can be organized ad-hoc to solve an urgent new issue.

After the event, the group is dismissed, remaining actions to be completed by some members or delegated to somebody.

Kaizen events (should) involve people working in the perimeter/ process and are considered subject matter experts. The event is driven by a moderator which most often takes leadership.

People from outside the perimeter are welcome for they have no preconceptions and their candor forces the others to explain the situation clearly, extensively.

Kaizen events are popular at executive level because they are limited in time, have clear objectives and can be measured in terms of return on investment.

Managers don’t like the idea to pay someone for non-productive work, non-framed continuous improvement activities are seen as recreation or cool hanging out.

Framed by a standard format, limited in time and under accountability of the moderator, a kaizen event is acceptable investment.

The limited time is not only to limit the costs and backlog while participants are gathering, the limited time is also putting pressure on them.

Kaizen events, kaizen blitz are often used to overcome resistance to change. The change is so quick that most opponents will realize the change or its implication too late to build up their resistance.

Going on with warfare example, it is like overrunning a defense line without spending time to convince defenders to surrender.

I have some reservations about kaizen events as they are too often lean disguises for productivity improvements betraying the kaizen spirit.

>More about downsides of kaizen events in the next post.
>related: what is Kaikaku?

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