10 Common Misconceptions About Lean Manufacturing

1. Lean production = volume production. In Taiichi Ohno’s Workplace Management he suggested that the Toyota system was ideally suited for low volume production, and not as well suited for the higher volume production that Toyota was shifting towards. In chapter 20 after describing the successful efforts at Toyota do Brasil to reduce lot sizes through changeover reduction, Ohno states:

Back when we started with the Toyota Production System, we would have demand for 3,000 to 5,000 vehicles per month, and a lot of variety. It was not so-called high mix low volume, perhaps it was medium volume, though there were some low volume items. So the Toyota System is a system that works very well when applied to mid-sized companies. What I mean by this is that the Toyota Production System was born in the days of 2,000 to 3,000 vehicles per month, so when production volumes are as high as they are today at Toyota, you do not really need to use this system to reduce cost.

The subtitle to Taiichi Ohno’s book Toyota Production System: Beyond Large-Scale Production in Japanese is 脱規模の経営をめざして and would be better translated as “Aiming for Non-Scale Management” or “An Escape from Scale-based Management” or “Towards Management Not Based on Scale”. Ohno was clearly saying the Toyota Production System is a way out of scale or volume-based production.
2. Japanese companies are Lean. There is nothing inherently Japanese about Lean manufacturing, nor are Japanese people naturally better at Lean than any other people. Just like Americans aren’t naturally better at heart surgery, even though the world looks to the U.S. for world class heart surgery. Both are historical accidents. Japanese companies tend to think long-term, and the system of lifetime employment does tend to support people development, so it is true to say that many Japanese companies have better groundwork to support Lean, but not true to say that most or even many companies are Lean in the sense that they are actively building and improving an operational model based on the Toyota house.
3. Lean manufacturing is a set of tools. Lean certainly possesses a powerful set of tools for problem identification, root cause analysis, and problem solving. However, Toyota Production System = Lean manufacturing, and the last word of the three in TPS is the most important.
4. You can do Lean manufacturing just for cost reduction. People will only do kaizen for a higher reason, beyond what is good for the company to what is good for their families, society and the environment. In the short term people may ask “What’s in it for me?” but this question is also the long-term question. Cost reduction, as a rallying cry, gets old. Lean manufacturing is about making the work easier and less frustrating so that time at work can be spent on what matters, serving customers and growing as people. Cost reductions will follow.
5. Assembly lines, work cells, work teams = Lean manufacturing. This is a variant of 3 above. The main difference is the perception that a certain arrangement of people, material and equipment represents what is Lean manufacturing. Creating cells and working in teams may be Lean, but the thinking behind why this is a good idea is the important thing, not the physical or organizational configuration. This is most often encountered at organizations where Lean has already been “done” but it is not working so well after a few months or years, leading to the “It must be because we’re different” illusion and stumbling block to Lean.
6. Lean = identify value by product, map value streams, flow, pull, pursue perfection. Popularized by Lean Enterprise Institute, this definition is not wrong, but is dangerously simplistic, leaving out quite a lot. The emphasis on value streams, flow and pull are somewhat redundant in that they are all dealing with the idea of overall optimization, which is important but is only one pillar (JIT) while leaving out the build-in quality pillar of the Toyota house. Perfection is not only unimaginable by definition to non-divine beings, but undesirable since it suggests an end point to kaizen. Can anything exist beyond perfection? There can be an “ideal” because by definition this is the best that we as humans can imagine, and a higher ideal can exist, to be re-imagined as we learn more.
7. Lean is the latest management fad. This may only be half of a misconception. It is certainly a management fad, and as fads go the popularity of Lean is bound to wane or at least take on a new and improved definition. As the term “Lean” is sure to be replaced with something more appropriate as people better understand what it is that makes companies like Toyota great. But Lean is no more the “latest” anything than the scientific method and a desire for social harmony are things invented in the last half century.
8. Lean is the elimination of waste. Much of Lean is about getting rid of waste (muda). There is also the elimination of variation (mura) and overburden (muri). Variation can result in overburden, resulting in waste. The elimination of waste is good shorthand for getting rid of the root causes, which include overburden (forcing a system to do something it is not designed to) due to variation (in customer demand, people’s ability, material quality, etc.), in order to build a stronger system. For most of us it is safe to stay focused on the elimination of waste for the early years on the Lean journey, with an eye on system-level causes of waste.
9. Lean dislikes computers and IT solutions. Lean does not discriminate against any technology that respects people and helps get rid of waste. A core Lean value is what is called genchi genbutsu in Japanese (actual place, actual product) which is often called “go see” in English. Management, and problem solving in particular, should be done on a “go see” basis to get the facts, live. Software solutions make it too easy to keep smart people from going to where the theory meets reality (products meet customers). Huge LCD screens for visual management may be gee-whiz for visitors to the factory, but white boards will actually get used by the team members to write down real problems that happened five minutes ago.
10. Lean + Your Favorite Buzzword Here = Great Idea! This is so-not-so and I think only the largest and most optimistic of consulting firms and manufacturing software solutions providers are still doing this, but there’s the occasional surprise like Lean Outsourcing or whatever to make one wonder. Maybe there is a huge Lean + YFBH consulting market, and TPS purists like us are missing out.

13 Comments

  1. Dan Markovitz

    June 25, 2007 - 7:20 am

    Jon,
    I agree with you regarding point #8 (Lean is the elimination of waste). There is so much more to Lean, not least of which is respect for people. The nice thing about focusing on waste reduction, however, is that the benefits are immediately visible and felt. And that’s the “sugar coating” to get people to invest in Lean both emotionally and intellectually.
    “Respect for people”? It’s hard to get most US companies to buy into this idea, when quarterly earnings and cost cutting are often the most powerful drivers in the business. But dangle the carrot of eliminating waste in front of management, and you’ll get their attention. And that’s at least the first step on the Lean journey.

  2. Chet Marchwinski

    June 26, 2007 - 8:50 am

    Hi Jon,
    You make a lot of good points in the list but I just wanted to calarify that #6 refers not to LEI’s definition of lean but to the five-step lean thinking process that Jim Womack and Dan Jones proposed to guide managers through a lean transformation. Our definition of TPS includes JIT and jidoka.
    Sincerely,
    Chet
    Chet Marchwinski
    Communications Director
    Lean Enterprise Institute

  3. Seb

    June 26, 2007 - 3:48 pm

    Jon,
    I agree with most of your list, especially the misconceptions of Lean only being for this or for that… Two comments though about your little list:
    1. Yes, the five principles promoted by the LEI are a little simplistic, but if you read the books it will become clear that they are by no means saying that you can actually achieve perfection. What they are trying to say is that by pursuing it (or what you call “the ideal”), one can get better and better in small steps. Personally, I always like to explain perfection with a continuous improvement culture, the attitude that you are never good enough, no matter how good you are at doing something. I made my first steps in Lean with the 5 principles and yes, there is so much more, but it is it a good way to start? I would say so. And that’s why I have my second comment/question:
    2. A lot of the misconceptions you write about are due to simplifications “Lean is just this” or Lean is just that”. But when asked the simple question “What is Lean?” What do you tell your customers, trainees, Kaizen participants?
    Great blog, love reading it.

  4. Erik

    June 28, 2007 - 10:38 am

    Jon,
    I am slightly confused by #1. In Workplace Management I do remember Mr. Ohno talking about how mass production is a fine system if and only if you can sell everything you make. Toyota was not in that position after the war, therefore TPS developed out of need.
    However, I’m confused by the part about “so when production volumes are as high as they are today at Toyota, you do not really need to use this system to reduce cost.” Is this true? At the currently high volumes that Toyota is faced with, is TPS less effective at reducing cost? Has Toyota arrived at a point now where the mass production system that they sought to compete with may be more ally than foe? Am I understanding that correctly? I’m quite sure that I’m missing something but I don’t know what.
    ありがとうございます。

  5. Jon

    June 28, 2007 - 12:56 pm

    Thanks for the question Erik.
    When Ohno said “when production volumes are as high as they are today at Toyota, you do not really need to use this system to reduce cost” it was 1987, not 2007.
    From his perspective in going through the boom years of 1950-1973 and then the “reduced volume” years in the 1970s post-oil shock, Ohno was saying that volumes were so high by the late 1980s that Toyota was achieving economies of scale to reduce cost and did not really need the Toyota system of high mix low volume capability, as he described in chapter 20 of Taiichi Ohno’s Workplace Management.
    I think Ohno was lamenting the fact that Toyota was able to profit through growth and losing focus on cost reduction through flow and flexibility. Even in 2007 this message is highly relevant, as many of the most senior members at Toyota are questioning whether Toyota has lost their way.
    どういたしまして。

  6. Ondrej Pinka

    October 9, 2007 - 1:33 am

    Dear Jon
    I am a complete novice to Lean world. Just finishing reading the Lean Thinking, I would like to comment on #6. I don’t think authors simplified all Lean to those five steps. My understanding is these are advices where to start, where to focus first when everywhere you look you find muda. I understand from the book that Lean is continuous, and never-ending process of improvements, in all areas that bring value to customer. For example if JIT brings no value to customer (theoretically), I would not bother. I hope I got the right idea of lean, being more a philosophy of living and doing things, not just set of tools (as from my experience many people think).

  7. Jon

    October 10, 2007 - 9:51 am

    Hi Ondrej,
    I still think the 5 steps are an attempt at simplification of the Lean thinking process. The authors of Lean Thinking coined the phrase “Lean thinking” so I can’t argue with that, but the Lean thought process seems bigger.
    Step 1 is good, and step 5 is good, but steps 2-4 seem arbitrary. “map value streams, flow, pull.” Why not “observe and document processes, expose waste, remove waste”?
    Between defining value and pursuing perfection / benchmarking perfection you could succeed by focusing on various other Lean principles or tools, not necessarily VSM, flow and pull.
    I think you comment that if JIT brings no value to the customer, you should not bother with it is partially correct. The customer might not care whether you build and deliver just in time but it may still be the cheapest way to produce, so there would be value to the producer (possibly definable as internal customer).
    You’re absolutely correct in that Lean is a philosophy of living and doing things, a never-ending process.

  8. Owen Berkeley-Hill

    November 1, 2007 - 8:00 am

    Jon,
    I am ambivalent about misconception 9. IT and Lean do have a problem of compatibility.
    On the one hand, why would any Leanie reject a tool (IT is a tool, is it not?) which could potentially improve quality, minimise or eliminate many of the Wastes, and reduce costs?
    However, IT does come with historical baggage which prevents a marriage with Lean Thinking.
    Through much of its history IT has been used to automate and eliminate jobs and show people the door (a higher purpose?). IT has been used to reinforce “Command & Control” Thinking (John Seddon): little room for the creativity necessary for a healthy Kaizen culture.
    Speaking of “kaizen”, most IT professionals break out in hives at the mention of the work: continuous improvement is often interpreted pejoratively as “Maintenance”; specifications must be carved in stone and signed in users’ blood before any work can start. Check any IT project’s business case: how many focus on making a business process flow flawlessly by minimising Waste? Does the latest IT fad, “Workflow” really flow? Does Workflow challenge management thinking by asking why an approval request needs to travel through 12 layers of management, rather than just trying to speed up the existing process through the purchase of yet more software?
    Take Poka Yoke for example. IT as a basis for the development of simple poka-yoke devices has potential beyond the price of rubies. But how many IT professionals understand the principles of Error Proofing? Many do, but this is usually the result of painful experience, not formal, and formative IT education.
    I speak as someone who spent 25 years in IT, and someone who struggled to encourage an illicit affair between the two sides. Think of the progeny! Wow!

  9. Jon Miller

    November 1, 2007 - 1:54 pm

    Thanks Owen.
    Your experience brings valuable perspective. Good questions. I don’t have all of the answers.
    My philosophy is that work is work and process is process. Lean is not prescriptive. IT folks naturally resist manufacturing solutions imposed onto them, just as manufacturing folks might scoff at software fixes to real-life problems.
    Is there a better way to do IT? If the answer is “no” then we have a big problem. If the answer is “yes” then it doesn’t matter what we call it.
    Misconception #9 may run both ways.

  10. George Friesen

    May 5, 2008 - 9:03 am

    As a consultant who has served clients in a variety of industries as they implemented the 5S System…typically as a first step in the implementation of other lean processes, it has been my observation that the greatest impediment to the successful use Lean tools is the failure of top management to understand that Lean is not primarily about work processes. Rather, at the heart of Lean are some assumptions about the nature of people that stand at significant variance from the assumptions of the mass production model. In addition, it has been my observation that for Lean to be successful the nature of the relationship between front-line supervisors and line workers needs to undergo a very significant transformation. If I were to be asked about the key blockers of Lean transformations in a workforce, I would say that they would be front-line supervisors. In my opinion, before an organization begins any sort of transition of Lean processes, they should provide training for the front-line supervisors in training on: 1) Lean Assumptions regarding Work and Workers; 2) Communication Skills; 3) Team Building; 4) Being an Effective Coach; 5) Change Management.
    On another topic relating to Lean. How ironic it is that Toyota got many of its ideas about Lean from books published by Henry Ford in the early to mid 1920s.
    George Friesen
    Business Practice Leader

  11. s k murthy

    May 18, 2008 - 8:03 am

    The TPS, LEAN, SIX SIGMA etc., all seem to cover/focus on manufacturing industries, whereas for the PROCESS industries the applicability would be slightly different in the sense that it would not be the individual machines or the operators but the entire stream of machines working in a coordinated fashion. Your comments please.

  12. Jon Miller

    May 18, 2008 - 4:15 pm

    Thanks for your question SK Murthy.
    For continuous process manufacturing the aim of lean / TPS / kaizen would be the same: to increase profitability and develop people by reducing variation, waste and overburden.
    Often the focus in process industries is on what are called the 6 Big Losses which comes from TPM (Total Productive Maintenance) and include breakdowns, changeover, scrap, yield, minor stops and adjustments. These losses can be reduced by focusing on the sources of variation, waste and overburden.
    The processes and equipment may be connected and coordinated, but the failure points tend to be discrete, thereby allowing problem solving in a similar fashion to discrete manufacturing. Also, there is nothing inherently different about the way you educate and train people to detect and solve problems in process v. discrete manufacturing.

  13. Bob MacPherson

    July 28, 2009 - 5:48 am

    As someone who has been trying to learn lean for over fifteen years (and a few years accidental/mandatory corporate exposure to six sigma during the evil reign of a book of the month club CEO in a previous job) may I now stand in applause for comment number 10! Lean Six Sigma is the Pet Rock of the Twenty First Century. They belong together as much as Rosee Odonnel and Geroge W. Bush do. (In my humble opinion)