Tips for Lean Managers

What About the 8th Waste?

By Jon Miller Updated on April 3rd, 2021

When learning to implement Lean manufacturing or Lean office principles one of the essentials is to develop a deep understanding of the 7 types of waste. Many people start working with the tools right away, value stream mapping or doing 5S activity without clearly linking this activity to waste reduction.

The concept of waste (Muda in Japanese) is common sense once it is explained to most people in a Lean manufacturing context. Yet because it is such a simple and universally acceptable idea, some people think it’s too simple and needs to be “improved”. This results in the addition of new wastes, anywhere from 1 to 13 new wastes in our experience.

The main reason we recommend staying with the original 7 wastes is to keep it simple. Other types of waste can almost always be included in one of the 7 types, or they are a cause of the waste rather than a waste itself. For example “complexity” is sometimes included as a waste, but this is more a cause of other types of waste such as transportation or processing waste or the waste of defects that result from complexity.

In the early days of developing the Toyota Production System some 50 years ago Taiichi Ohno identified the original 7 types of waste. He is said to have used the Japanese expression “Even the best person has 7 bad habits” as an inspiration. One question I ask is “If after more than 50 years of waste elimination Toyota hasn’t added new wastes, do you really need to?” While that might stump some people, it doesn’t really help them explain to others why there are 7 and not 8 wastes.

The question we hear the most is “What about the 8th waste, the waste of peoples’ unused creativity?” Some texts on Lean have added this 8th waste. The so-called 8th waste usually describes the fact that the creativity or ideas of the people are not being used to improve the work. While this is clearly a loss that Lean and Kaizen must correct, it is does not fit with one of the 7 types of waste that you can see in a production of service process.

If people’s ideas are not being utilized, this means that you will have more of the 7 wastes (defects, motion, inventory, transportation, overproduction, processing, waiting). It’s important to understand that certain things (like underutilized creativity) cause waste, and waste causes losses in profitability.

In other words:
Unused creativity > less effective processes > 7 wastes > lower profitability

There is an important cause and effect relationship that needs to be understood. Lean implementation is much more about changing behaviors and how people think about work than about actually changing ‘things’ (procedures, factory layout, systems, etc.). The 7 wastes are the link between the root causes (human behaviors) and the loss of profit. Thinking deeply about the 7 wastes and learning to see and measure them in every process is the key to taking quick, effective kaizen action.

  1. Vincent Stamper

    July 20, 2006 - 12:58 pm

    I think you need to check the Toyota employee handbook, as cited in “The Toyota Way” by Dr. Liker, in which the 8th waste is listed as “Unused Employee Creativity”. Mr. Cho, did add it in their official literature (although they jokingly practice a “kinder, gentler” lean than Mr. Ohno did). It doesn’t roll off the tongue like the other seven, but speaks more to the culture of Toyota than the practices.
    Could it be that Taiichi didn’t include it in the original seven because he felt it was ingrained in their culture, and therefore assumed?
    It is my opinion that most organizations do not include the eighth waste because it speaks to something deeper within their culture and leadership structure.
    As all of us in change leadership know, it is much easier to adopt practices than to change culture. But is something like that sustainable, or superficial?

  2. Jon Miller

    July 20, 2006 - 8:18 pm

    Hello Vincent,
    Dr. Liker must have access to a much more recent edition than I do. Or it may be a matter of translation.
    Respect for human creativity is definitely a Toyota value, though I have not heard it called a waste outside of books written by Doctors Womack, Jones and Liker.
    At Toyota they call TPS the Thinking People System. They want people to think and to change, not just mindlessly adopt their practices.
    You make a very good point.

  3. Kashif Butt

    August 15, 2007 - 2:19 am

    Hi All,
    Can anyone explain the difference between KAIZEN & MUDA?

  4. Jon

    August 16, 2007 - 7:33 pm

    Hi Kashif,
    Kaizen is “to change and make good” or “continuous improvement”.
    Muda is “waste”.
    You do kaizen to get rid of muda.

  5. faisal

    August 17, 2009 - 8:05 am

    actually i’m doing my final year project about this topic
    the implementation of lean manufacturing..i face some problem to focus my final year project…can i get everyoe help me doing my research..
    i would like to create something new for my final year project…somebody can help me can email me at [email protected] thanks

  6. Deepu

    March 18, 2010 - 9:35 pm

    i’m doing final year project,,,, can anyone explain about the 8th KAIZEN waste

  7. mdg

    June 19, 2022 - 10:45 am

    When you identify the wastes, in order to eliminate them do you do a root cause analysis or 5 why’s? What tools do you use?

    • Jon Miller

      June 19, 2022 - 11:08 am

      Yes. Sometimes the countermeasure is obvious and doesn’t require root cause analysis. If you observe that motion waste is a big problem and people are searching or reaching, declutter and organize so everything is within reach. Other times defects may be a big waste, but reasons are not obvious so root cause analysis is needed. In some cases we hold too much inventory “just because” or “just in case”, for no good reason. In other cases, there are changeover times, supply problems etc. to understand before reducing inventory. It’s situational.

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