Best Practices in Lean Six Sigma Process Improvement: A Deeper Look

Citation

Weinstein, L.B. (2009), "Best Practices in Lean Six Sigma Process Improvement: A Deeper Look", Benchmarking: An International Journal, Vol. 16 No. 4, pp. 562-563. https://doi.org/10.1108/14635770910972469

Best Practices in Lean Six Sigma Process Improvement: A Deeper Look is the latest book by Dr Richard J. Schonberger, author of Japanese Manufacturing Techniques: Nine Hidden Lessons in Simplicity (1982), World Class Manufacturing: The Lessons of Simplicity Applied (1986), World Class Manufacturing Casebook: Implementing JIT and TQC (1987), Building a Chain of Customers (1990), World Class Manufacturing: The Next Decade (1996), and Let's Fix It: Overcoming the Crisis in Manufacturing (2001).

In his most recent book, Dr Schonberger takes a broad look at the topic of lean as a competitive strategy. He begins by describing how organizations can achieve lean through implementation of what he refers to as the lean core‐practices, including kanban‐based pull systems, quick setup, small lot size, supplier partnerships, and product design. He looks critically at the best‐accepted concepts for process improvement and explains how organizations often misuse them. He calls for implementation of lean‐focused accounting systems and more effective performance metrics. He describes the necessity of installing a customer‐focused culture that practices continuous process improvement. Throughout all of his discussion, Dr Schonberger provides frequent examples of companies succeeding – and failing – in their efforts to implement lean.

Schonberger asks “How does an organization get lean?” Leanness may be achieved through acquisitions, mergers, by hiring a manager with lean expertise or experience, or learning to design products suitable for lean manufacture and assembly. He describes how some organizations have designed products and manufacturing facilities that support lean operations. He describes how organizations must – and have – integrated their suppliers and customers into a synchronized lean enterprise system.

Dr Schonberger bases his evaluation of an organization's leanness on its inventory turnover ratio – the cost of goods sold divided by the value of inventory. He evaluates each organization's long‐term performance by converting its turnover ratio over time into a numerical score. He uses a similar approach in his World Class Manufacturing Casebook, in which he applies several forms of ratio analysis to evaluate an organization's just‐in‐time process performance. By the author's own admission, this ranking system based on inventory turnover is flawed:

The inventory trend […] is indicative, but sometimes not a fair and accurate gauge of excellence in lean management. Product lines change, acquisitions and divestitures, offshore moves, and so forth may skew inventory performance for a few years.

Nevertheless, the author clearly demonstrates that there are lessons to be learned by looking at this metric – however with the caveat that while we may use inventory as an indicator for the health of an organization, cutting inventories without process improvement may only result in shortages and lost customers. Lean must be the objective, not the tool.

This book provides valuable lessons for both the student and practitioner of lean management. The author's approach is to introduce the basic concepts of lean and then to describe how organizations use these concepts to achieve certain results. It is the author's insights into the activities of these companies that make this book so interesting. Throughout the text, Dr Schonberger provides numerous anecdotes about organizations' efforts to achieve leanness, using his extensive database of 1,200 manufacturers, retailers, and distributors in 36 countries to provide interpretations and justifications for companies' performances.

Despite its title, the author writes very little about using the six sigma process to achieve leanness. I expected that the book would include more information regarding how organizations have successfully used six sigma techniques to achieve lean breakthrough or how practitioners might apply the six sigma DMAIC process to identify opportunities to implement lean approaches. Nevertheless, the author provides a valuable contribution to the body of research in lean and I would recommend this book to both practitioner and researcher.

For the reader who is interested in learning more about the techniques of lean management, I would also recommend the series of Shingo Research Prize‐Winning Workbooks available through the Lean Institute (www.lean.org). These provide an excellent introduction to the application of lean techniques.