During the past dozen years, companies I have worked with have, between them, completed more than 1,000 lean Six Sigma (LSS) projects. Based on this experience, I’ve found that improvement projects can be broadly categorized into three types: quality-improvement, revenue-enhancing, and cost-saving.

A brief description of the three types of improvement projects, and the strategy that these businesses followed, are given below.

Quality-improvement projects

The quality-improvement project is the quintessential LSS project. About 60 percent of our projects were of this type. A quality-improvement project typically attacks a defect or customer complaint, and seeks to reduce, eliminate and, ideally, prevent the defect. Relevant data are usually available for such projects. The heart of such a project is data analysis to find out the root cause of the defects. Once discovered, the root cause is eliminated by a change or improvement in the process, so that the problem doesn’t recur. This process-change is often some form of poka-yoke or mistake-proofing.

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