Quality Scan: Reconsidering Waste
As usual, I enjoyed the May 2007 edition of Manufacturing Engineering magazine. Being a lean practitioner associated with the SME/AME/Shingo Lean Certification program, I'm especially interested in ME magazine's frequent articles on Lean thinking.
The May issue's "Quality Scan" article, entitled Waste Remains the Enemy caught my attention. I took exception to several aspects of the otherwise fine article by Geoffrey Mika. In it, the author adds to Taiichi Ohno's original seven forms of waste, introducing workforce underutilization, improper use of computers, and working to the wrong metrics. In my opinion, two of these forms of "waste" claimed by the author are more accurately contributing factors, and one is, I believe, dangerously worded and can draw readers into a common pitfall that hinders effective Lean thinking.
To begin with, waste is "an activity that consumes resources but produces no value for the customer." This definition comes from The Lean Enterprise Institute's (Cambridge, MA) book Lean Lexicon. Mr. Mika's "Improper Use of Computers" waste, therefore, is potentially valid, because misuse of the computer will consume resources and may not produce customer value. However, there is nothing special about a computer in business operations. Any tool—a milling machine, a crescent wrench, a typewriter—can be used in a way that produces no value for customers. Why does the author see it as necessary to elevate the computer to a special position? As Mika states, "Computer surfing today is what reading the newspaper or magazine was 20 years ago." Using this logic, therefore, 20 years ago we should have had added "Improper Use of Newspapers" to the list of lean wastes.
Secondly, "Working to the Wrong Metrics" is not a waste, but it is a common reason why waste is created. People often confuse waste with a condition, state, or contributing factor to why the waste exists. It appears that that Mika has not drawn a sharp distinction between waste and cause of waste. For example, management inattention, improper calibration, and not hearing the voice of the customer are all common undesirable conditions that typically contribute to the existence of waste, but they do not themselves fit the definition of waste. As a further example, if I see a waste of excessive work-in-process, I can ask, "Why does that exist?" The cause may, in fact, lie in working to the wrong metrics.
Thirdly, Mr. Mika offers "Workforce Underutilization" as a waste. His choice of words here is unfortunate. Since the first development of the Toyota Production System, several practitioners have amended the original seven types of waste. Few of these add-ons have withstood the scrutiny of the practitioner field. "Unapplied knowledge" was added by one author not too long ago, and "knowledge disconnects" was introduced by Pascal Dennis (the author of Lean Production Simplified, Productivity Press), and appears to be gaining some acceptance within the lean community. Mika's terminology includes the term "utilization", which is too frequently associated with a mindset that is contrary to lean production.Traditional mass producers typically aim to maximize the utilization of their equipment and manpower assets.They typically do so by seeking to lower product unit costs. This attitude, however, often comes at the expense of making product only when the customer wants it, in the quantity the customer wants.
By using the term "Workforce Underutilization", Mika comes dangerously close to inadvertently reinforcing a belief system that contributes to overproduction and excess WIP inventory. Clearly, as I read the text, the author is referring to the unapplied knowledge and creative potential of workers. The term he has chosen is, however, loaded with other meaning for readers who are still mired in a traditional production mindset.
Again, Mr. Mika's article is of value. His examples and other topics are well-written and support understanding. But I must respectfully disagree that the three additional forms of waste he coins deserve equal standing among Ohno's original seven wastes.
I offer these comments in the hopes of avoiding confusion among lean practitioners. Many struggle with basic terminology and interpreting what lean truly means.While the author's article was insightful and informative, I felt it did not clarify the issue of defining waste, and instead may confuse readers.
This article was first published in the September 2007 edition of Manufacturing Engineering magazine.