My blog’s third birthday

January 2014 – January 2017, my blog is now online for 3 years and counts 347 posts.

Thanks to all of you my audience is gently growing on this blog, as well as on my Youtube channel and on tweeter. All organic!

What is the most read here?

According to the stats, Constraint vs. bottleneck is the absolute winner, ahead of 3D Printing and Porter’s five forces ranking second.

Then comes a string of posts related to the Logical Thinking Process and the popular Goal Tree.

What’s on schedule for 2017?

Well I have a huge inventory of titles, topics, half-written posts on the various subjects I’d like to share: Lean Management, more about Logical Thinking Process and Theory of Constraints, my prospective survey about the future of manufacturing and much more.

I’ll try to post on a regular basis and bring some value-added content. You are welcome to give me feedback in the comments.

Hope to see you here!

5View Christian HOHMANN's profile on LinkedIn

Bill Dettmer and David Poveda share views about planning

David Poveda is a Colombia-based consultant, Owner and  Director of FLOWING Consultoria. David is well-known for his successful implementations of Theory of Constraints (ToC) and Lean-based solutions, and his expertise about Demand Driven MRP (DDMRP).

Just before the Logical Thinking Process training in Paris, in June 2016, he paid a visit to Marris Consulting and met Bill Dettmer. Both agreed to share thought about various subjects and in front of recording camcorder.

In this 10 minute video, David shares his views about planning techniques and somewhat surprisingly links ToC’s Thinking Processes to planning, especially Bill Dettmer’s Goal Tree .

According to David, the Thinking Processes should be called “the real planning processes“, because they are a complete planning and execution methodology. Bill is somewhat taken by surprise and explains the origins of his Logical Thinking Process (LTP) being in complex problem solving, but realizing with David’s inputs that changing what is done requires competent planning.

David goes on and explains that a Goal Tree is a planning tool for smaller projects as well, and many of David’s clients agree about not knowing how to plan. Therefore the LTP should be taught more widely.

We are all Lean now. What’s next?

Every once in a while, for nearly 30 years, the question arises: “what’s the next big thing after Lean?”, suggesting that the askers are done with Lean. We write July of 2016 and it seems that everybody is Lean now.

Many people have been repeatedly exposed to Lean methods and tools, have been involved in Lean workshops, kaizen events, sketched Value Stream Maps and identified wastes, sorted out, cleaned up and rearranged stuff 5S style.

They have seen improvements, celebrated the workshop’s success and were dismissed with a feeling of mission accomplished. Others didn’t see a clear outcome, noticeable improvement or a sustainable result and resumed their regular work.

Both may have a legit feeling of being done with Lean, the first because their objectives were met, the latter because Lean doesn’t work.

Almost everybody has heard about Lean, in good or bad, in manufacturing or administration, in hospitals or software development. Lean is a word that found its way into the business lingo, and hearing it often makes it familiar.

There is also the growing impatience as everything speeds up and the instant satisfaction sought by everyone becomes commonplace. Few people are able to commit to a very long and tedious journey towards excellence in the Lean way, most would prefer periodical quantum leaps. Just as they replace their smartphone from one model/generation to the next, keeping up with fashion or state-of-the-art technology.

Of course we are far from done with Lean and very very few companies I’ve visited can claim being Lean. Nevertheless I can understand the fading interest in Lean and the need to reinvigorate it with something new and effective.

Something new means something new to people they didn’t know about until now, not necessarily new per se. Effective means bringing positive results system-wide, not a local optimisation.

My advice would be to consider Throughput Accounting, Critical Chain Project Management and the Logical Thinking Process.

This is not about the next big thing AFTER Lean but the next big thing WITH Lean!

Throughput Accounting (TA) is not really accounting but rather a Throughput-based decision-making approach. In a nutshell, TA shifts focus from cost reduction to Throughput increase and optimization. Follow this link to know more.

Critical Chain Project Management (CCPM) revisits Critical Path Method, the prevalent project management method that failed so far to get developers and project teams to finish on time. CCPM makes sure that projects finish on time and that, thanks to continuous improvement Lean and CCPM style, project durations can be shortened in future.

Logical Thinking Process (LTP) copes with system-wide complex problems. It provides logical tools and methods to surface and neutralize false assumptions, beliefs, conflicting objectives and the like that hinders the organization achieving its goal.

Giving a try with any or all TA, CCPM and LTP, will reveal new potentials and focusing points for Lean to exploit them. Lean isn’t gone soon.

Bandeau_CH160608View Christian HOHMANN's profile on LinkedIn

My takeaways from throughput accounting, the book

I knew the author, Steven M. Bragg from his podcast series “Accounting Best Practices with Steven Bragg” before I came across his book “throughput accounting, a guide to constraint management” published by Wiley & sons, 2007.

Book presentation

The hard cover book has 178 pages, 10 chapters, easy to read in neat presentation and legible fonts, with numerous tables, graphs and illustrations to back up all the provided examples and case studies.
It claims to contain the tools needed to improve companies performance for accountants, financial analysts, production planners or production managers.

The book starts head on by introducing the basics of Theory of Constraints (ToC) in an uncommon, and for me daring way: explaining very briefly the Drum-Buffer-Rope (DBR) logic, in chapter 1 (page 1!).

It is daring because it’s a shortcut putting DBR upfront when it’s usually presented to newbies (long) after explaining the bottleneck concept and the differences between traditional manufacturing, trying to run every resource at full utilisation rate, versus the ToC approach where “only” the bottleneck matters (this is another shortcut, but of mine…).

It goes on with presentation about the different types of constraints, not all being bottlenecks, discussing the nature of the constraint (page 5). The Throughput Accounting (TA) KPIs are presented page 7 and 8 before diving into the financial aspects of TA.

Chapter 2 is about Constraint Management in the factory, starting with how to locate the constraint and how to manage the constrained resource. The various hints are clearly targeting managers or readers keeping some distance from shopfloor as they give enough insight without being too detailed. No people will go through and get bored, the various hints are condensed within few lines, without giving up anything important.

Four pages deal with policy constraints, again something of interest for managers and readers that may have influence within their own organization to educate their colleagues about the drawbacks of some policies and hopefully change them. The importance of constraint buffer comes page 25 followed by the importance of proper batch sizes and machine setups.

Chapter 3 is about throughput (TA) and traditional cost accounting concepts and starts with the emphasis on cost versus Throughput and goes on with all the consequences describing why traditional cost accounting – companies that means – is suffering from several problems.

This chapter is important for people not very familiar with accounting, especially in operations, because it explains some of the decisions that make no big sense when considered from operations point of view. It is also important for those familiar with traditional cost accounting for to understand the limitations and problems brought up by that approach.

Chapter 4 is about Throughput and Financial Analysis Scenarios and from page 59 to 86 take the readers through 14 different scenarios, from Low Price, High Volume Decision to Plant Closing Decision.

Chapter 5 is on Throughput in the Budgeting and Capital Budgeting Process, chapter 6 about  Throughput and Generally Accepted Accounting Principles and chapter 7 about Throughput and Control Systems.

Chapter 8 details Throughput and Performance Measurement and Reporting Systems, interesting because it links the operations’ reality to usable KPIs, e.g.

  • Ratio of Throughput to Constraint Time Consumption
  • Total Throughput Dollars Quoted in the Period
  • Constraint Utilization
  • Constraint Schedule Attainment
  • Manufacturing Productivity
  • Manufacturing Effectiveness
  • Order Cycle Time
  • Throughput Shipping Delay
    And more.

Chapter 9 is named Throughput and Accounting Management and addresses 12 decision areas among which: Throughput Analysis Priorities, The Inventory Build Concept, Investment Analysis, Price Formulation.

Finally chapter 10 presents 7 Throughput Case Studies each of them in a couple of pages.

My takeaways

The book is easy to read and to all concepts are easy to understand thanks to the simple ways the author puts them. Not being an accounting specialist at all, I always liked the simple, pragmatic and concise ways Steven Bragg explains accounting rules or practices. This book is not different.

Reading “throughput accounting, a guide to constraint management” reinforced both my knowledge and my interest in throughput accounting, as well as the conviction about throughput accounting being a powerful and crucial decision-making approach.

I’ve marked dozens of pages with sticky notes highlighting my points of interest and/or inspirations for posts on my blog, reinforcing my consulting approach, etc.

Throughput accounting

Almost all companies have their management heavily influenced by traditional cost accounting and most of them make ill-oriented decisions. With the book’s content help, it is easier to explain to CFOs and CEOs why their decisions are biased by false assumptions or outdated rules, something that can be quite shocking to them.

The book doesn’t come cheap, but as it explains, quit reasoning in terms of cost savings and consider how much (intellectual?) Throughput it can leverage.

Bandeau_CH160608View Christian HOHMANN's profile on LinkedIn

What is Throughput Accounting?

Throughput Accounting (TA) can be understood as a simplified accounting system based on Theory of Constraints (ToC) principles. TA makes growth-driven management and decision making simpler and understandable even for people not familiar with traditional accounting.

Beyond simplifying, TA has a different approach compared to traditional accounting. The latter will focus on cost control (cost of goods sold) and minimizing the unit cost while TA strives to maximize profit.

Throughput Accounting sets the base for Throughput Analysis, helping to make decisions in the ToC way.

Simplifying accounting

Throughput Accounting will probably not replace GAAP in short nor medium term, but provides a limited set of simple KPIs, sufficient to:

  • Manage and make decisions in a growth-oriented and ToC way
  • Allow faster reporting and near to real-time figure-based management
  • Help people in operations to understand the basics of accounting
  • Set a common base for controllers and operations to discuss decisions, investments, etc.

Throughput Accounting uses 3 KPIs and 2 ratios:

Throughput (T)

Throughput, defined as the rate of producing goal units (usually money) and translates as revenue or sales minus totally variable expenses in accounting terms.

Totally variable expenses can be simplified to the cost of direct materials because labor is nowadays paid on a (relatively) fixed amount per time period, hence a constant expense to be considered as part of Operating Expenses.

Operating Expenses (OE)

Operating Expenses are all expenses, except the totally variable expenses previously mentioned in the calculation of throughput, required to run and maintain the system of production. Operating Expenses are considered fixed costs, even so they may have some variable cost characteristics.

Investments (I)

Investments, formerly call Inventories, is the amount of cash invested (formerly “tied”) into the system in order to turn as much of the Investments into Throughput as possible. This encompasses the stored raw material waiting to be transformed into sellable products as well as investments in capacities / capabilities to produce more units.

Net Profit (NP)

Net Profit is defined as Throughput minus Operating Expenses, or Sales – Total Variable Costs – Operating Expenses.

Return On Investment (ROI)

Return On Investment is the Net Profit compared to Investments (ROI = NP/I).

Drivers for achieving the Goal

Throughput Accounting offers a simplified way to identify and use the drivers to achieve the Goal, assuming the Goal is to make money now and in the future.

In a very simple way this can be summarized by the following picture which means strive to maximize Throughput while minimize the Operating Expenses and Investments.

ToC practitioners recognize that Throughput has no limit while Operating Expenses and Investments have limits beyond which no safe operations can be further envisioned.

The priority focus on improving T (focusing on the constraint exploitation) rather to go for all-out cost cutting explains the (usually) superior results when going the ToC way compared to unfocused improvements.

Throughput Accounting KPIs can be presented in a Dupont-inspired model in order to make the levers and consequences clear. (graphics to come)

Throughput Analysis

Beyond the simplification compared to traditional accounting, Throughput Accounting sets the base for Throughput Analysis, helping to make decisions in the ToC way.

Reminder: in a system with a capacity constraint, the Throughput is limited and controlled by the sole constraint. As the capacity is fully used and no spare is available to exploit, what goes through the constraint must be chosen wisely in order to make the best use of this very precious resource.

It becomes obvious then that utmost attention must be paid to maximize the passing of the highest profit generating products through the constraint. The decision making is then based on the Throughput per constraint minute rate. The higher the T/mn, the better.

Other decisions Throughput Analysis helps to make are about anything likely to alter the Throughput, Operating Expenses or investments. Basically, any incremental increase of OE and/or I should lead to an incremental increase of T.

Conversely any decrease of OE and/or I should NOT lead to an incremental decrease of T.

This post is partly inspired by the work of Steven Bragg. I recommend his blog and post about Troughput analysis

Bandeau_CH40_smlView Christian HOHMANN's profile on LinkedIn

Schragenheim’s concise history of constraints

The definition of a constraint in Theory of Constraints (TOC) has varied as the corpus grew and matured. Still today it is confusing for newbies to sort out what is meant with “constraint”, depending how they got their basics in TOC.

Thanks to Eli Schragenheim, one of TOC’s founding fathers, and the related post on his blog, the reader can understand how and why the definition varied over time.

I strongly recommend to read Eli’s post: A concise history of constraints

TOC, Lean and aviation MRO

In a previous post, “CCPM helps shorten aircrafts MRO”, I explained the benefits of Critical Chain Project Management (CCPM) for reducing the aircraft downtime during their mandatory and scheduled MRO.

If CCPM is great and helps a lot meeting the challenge, it will not squeeze out every potential improvement, thus time reduction, on its own.

As I explained in my post Critical Chain and Lean Engineering, a promising pair, “What CCPM per se does not is discriminate added-value tasks and non added value, the wasteful tasks listed in a project in a Lean thinking way.

Conversely, if wasteful tasks remain in the project network, chance are they will be scheduled and add their load (and duration) to the project.

That’s why in aviation MRO (as well as in other businesses), Critical Chain Project Management will not be used as a stand alone but in conjunction with other approaches, like Lean and Six Sigma.

Lean mainly will help to discriminate value-added from non value-added tasks, especially those on the Critical Chain, making them high priorities to optimize, reduce or eliminate.

We did not differently when we started with our client Embraer and while in their service center, I placed Philip Marris in front of the camcorders to present, in situ, two books related to TOC, Critical Chain and Lean in aviation MRO (aircraft Maintenance, Repair and Overhaul).

Note: Critical Chain Project Management is part of the Theory of Constraints Body of Knowledge, hence the title of this post where “TOC” is referring to CCPM.

Chris Hohmann

View Christian HOHMANN's profile on LinkedIn

TOC-based decision for best product mix

Theory of Constraints (TOC) provides a framework to identify, exploit, set pace and elevate* the constraint, or put in simpler words: identify the bottleneck in the process and make the best with it.

*Identify, exploit, subordinate, elevate and prevent inertia are known as the “five focusing steps” of Theory of Constraints.

In this constraint or bottleneck-centered approach, the aim is to give this peculiar resource a privileged treatment as it controls directly the whole system Throughput, hence the profit.

But working on the constraint capacity is not enough to maximize Throughput, the product mix is also very important.

Theory of Constraints therefore developed Throughput Accounting in order to cope with issues when making decisions based on traditional accounting and a new way to make decisions regarding product mix.

This video is a 49mn course about TOC-based decision for best product mix by Prof G. Srinivasan, IIT Madras


View Christian HOHMANN's profile on LinkedIn

What keeps TOC confidential? (and me angry)

It is one of the frustrations for Theory of Constraints (TOC) enthusiasts: why is their beloved business philosophy so barely known?

No other, neither Lean nor Six Sigma had such a visible high-flying banner like “The Goal”, the (probably) first business novel*, sold over 6 million copies so far. If readers have been so many and as it is reported so thrilled by the content, how come only very few people know anything about TOC?

*The Goal is a business novel written by Eliyahu Goldratt and Jeff Cox.

In this video interview, Nicolas Hennion shares his views, answering Philip Marris’ questions.

The first question about the name “Theory of Constraints” was also discussed with Bill Dettmer, another TOC expert with a pragmatic point of view.

I totally share Nicolas’ frustration about TOC Body of Knowledge being overprotected and monetized.

In my case, I stopped my learning journey in the mid-1990 when Internet was still young and not that populated with available free material as nowadays, Amazon did not exist and buying books from foreign countries (remember I am a Frenchman) was expensive and complicated. I resumed studying TOC and the Thinking Processes developed in between in around 2010, buying carefully chosen second-hand books, still shockingly expensive.

I estimate I’ve lost 10 years in my TOC learning journey, being disappointed about the difficulties and costs to get to the educational material. I turned to Lean instead, and did well.

When the TOC old guard wonders why TOC is still confidential, they should rewind Nicolas’ interview and try to understand the way the younger generations operate; networking, sharing, hacking open source style.

Food for thoughts…

Related: Theory of Constraints is something great, except for its name


Bandeau_CH40_smlView Christian HOHMANN's profile on LinkedIn

Critical Chain and Lean Engineering, a promising pair

Critical Chain Project Management (CCPM) has proven its effectiveness to terminate projects on time and even quite often before estimated finish date.

In development, engineering or Maintenance Repair & Overhaul (MRO), using CCPM can give a significant competitive advantage.

It can outperform slower competitors, earn premium for faster achievement and/or allow multiplying projects within similar timeframe and often with same resources.

CCPM is the perfect companion for Lean Engineering, giving the means to win the race-to-market and multiplying new product launches.

True Lean Engineering is something long to develop and “install”, it’s about learning and developing a reusable knowledge base as well as turning engineers into Lean thinkers.

Terminating projects earlier and multiplying them offers the learning opportunities to test and gather knowledge.

CCPM is therefore a good Lean Engineering “forerunner” giving a competitive advantage faster than the sole Lean Engineering initiative.

What CCPM per se does not is discriminate added-value tasks and non added value, the wasteful tasks listed in a project in a Lean thinking way.

Of course, when CCPM takes care about the capacity constrained resources, it invites to check the content of the tasks and scrutinize the proper use of those precious resources, thus calling for Lean-minded scrutiny.

CCPM acts then as a focusing tool for Lean-minded analysis and improvement.

These two, Critical Chain Project Management and Lean Engineering, seem to make a fine, promising pair.
Something to consider.

Bandeau_CH40_smlView Christian HOHMANN's profile on LinkedIn