Mike Micklewright: Why Is Quality So Rarely Central In Lean? By Mike Micklewright, Author of ‘Out of Another @#&*% Crisis!’ – Last updated: Sunday, April 11, 2010 – Save & Share – One comment

I see so many internal Lean “experts” using “Lean” as a means to increase efficiencies and productivity, and therefore, reduce costs.  They still do not see the connection to quality.  They see quality and the reduction of variation in significant product characteristics as something that is outside of the Lean scope and something that should be handled by the quality folks independently of the lean effort.  What a shame!  If you agree with this observation, why does this exist and what can we do to change this perception?

Art Smalley Response:

This topic strikes a chord with comments I have made in the past regarding the state of Lean at least in the United States. Unfortunately I do feel that the Lean movement is often guilty of under emphasizing quality at times. Of course this is just a broad characterization and I am not speaking about my colleagues here on this site or directly about any company in particular. Let me try and explain my viewpoint.

The Toyota Production System for many years was depicted as having two pillars. One was the famous Just-in-Time Pillar and the other was the less well understood Jidoka (Build in quality / Separate man from machine) Pillar. The Jidoka concept is actually the older of the two dating back to the early 1900′s on looms that Sakichi Toyoda and his son Kiichiro designed. The Just-in-Time concept was coined inside Toyota in 1937. Of course Toyota was not great back then at either pillar by modern day standards but interestingly the Jidoka concept is the older of the two.

In the 1960′s Toyota recognized it had severe quality shortcomings in both its products and manufacturing quality. Eiji Toyoda directed the company to implement a TQC (Total Quality Control) program in 1962. Here is an early example of front line involvement from an engine plant. The operator is charting information on a control chart. (Click here to see the actual chart in Japanese.)

In just a few short years of diligent effort both product and manufacturing quality was greatly improved in the company. Defects were halved in a few short years and export to the United States slowly became a reality. By 1965 Toyota was awarded the Deming Prize for Quality. Continual progress on this front eventually drove Toyota to world class levels of quality by the 1980′s and 1990′s. (Of course I realize that today is a different story and Toyota is under criticism on the quality front but that is another post.)

Regardless Toyota benefited from decades of statistical quality control and statistical process control work. By the time I worked for the company the process capability was extremely highly and often in the 1.5 or 1.67 CpK range. Of course however problems still happen even with that level of capability. Here is a link to a Quality Control Circle presentation from a year or two ago that tackles a process with a 0.05% scrap problem on a connecting rod line in an engine plant…I bet most companies would like to have a 0.05% scrap problem that has to be tackled by such an effort???

So Quality has always been a big part of the Toyota Production System from its inception in the loom business, through its early automotive days, and up until the present time. That aspect has always been a constant fact for the company’s history. However I can not always say the same about Lean in the rest of the world.

TPS was introduced to the external world in publications starting around 1973. First Toyota drafted an internal manual for training purposes. In the mid 1970′s a couple of presentations were written up for international conferences and journals by key managers such as Fujio Cho. By the end of the 1970′s Taiichi Ohno had written his book on TPS and Shigeo Shingo had offered up his view points from visiting the company as well.

In the 1980′s TPS gained some traction in the United States as various companies interacted with Toyota or toured their facilities. External parties started to write books about the company in this decade and much was made of its “Kanban” system (although Kaban was just a tool to control production), 5S, Standardized Work, Single Minute Exchange of Die (SMED), and other tools. Unfortunately little mention was made of quality in these “tool” focused books for whatever reason. I suspect that since most quality tools came from the western world already those items just did not sound different enough to create any marketing buzz…

In the 1990′s the term Lean of course came into full force and much more came to be known about the system through both publications and interaction with various parties. By the 1990′s a niche consulting boom had opened up in the area of TPS implementation and Kaizen workshops. Topics such as 5S, Standardized Work, Pull Systems, SMED, and other topics were driven home often in week long events often called Kaizen Blitz Workshops or other such names. Quality was often lacking as a targeted goal in these efforts although I have no doubt that quality was often improved at the margins as a result of these workshops.

By the time the year 2000 had rolled around a new trend had emerged in TPS implementation called Value Stream Mapping. The tool was intended to take away some of the process focus and get practitioners focusing on the flow of product from raw material to finished goods and providing value to the customer. This reorientation succeeded tremendously in changing the perception of Lean away from “events” like 5 day workshops and more towards improving the overall flow of operations.

Unfortunately this reorientation still did not place as much emphasis on quality or process capability as I would like to see. I’ve always felt in hindsight that Lean does a good job with the Just-in-Time Pillar of TPS but it does not do justice to the Jidoka Pillar whatsoever. Missing still in many companies is the Juran Trilogy of Quality Planning, Quality Control, and Quality Improvement that Toyota was once famous for before its recent spate of problems.

Also in this past decade we have seen the rise of Six Sigma programs around the world as a tool for improvement. Indeed many companies practice “Lean Six Sigma” as a hybrid approach. If Six Sigma programs truly focused on quality and process capability I’d feel a lot better about the state of affairs. Unfortunately Six Sigma as often practiced has morphed into a cost cutting program where Black Belts run special projects targeted at saving the company specified amounts ($250,000 in large companies I have visited for example and smaller amounts in others).

So where does that leave us today? Some companies do a great job with quality while others struggle. In theory Lean purports to be about value to the customer but in reality most programs I visit are heavily focused upon the concept of flow, pull systems, standardized work and people involvement etc. There is nothing wrong with any of these tools. I just know from experience they are generally insufficient to arrive at world class quality or achieve the Jidoka concept in a process. I am confident that eventually the field will level however and more emphasis will be placed upon Quality and Jidoka in Lean programs. The reality that this question is being openly asked in a forum such as this one to me at least is a step in the right direction.