It occurs to me that sometimes it helps if you clarify just what the hell you are talking about… In our book, we discuss six sigma in the chapter on quality; and explain lean principles and practices in the chapter on lean manufacturing. But increasingly there has been a coming together of these two philosophies, so that the tools and techniques each deployed are being used interchangeably. We saw this in the recent blog we posted on Starwood Hotels (16 February 2015). And the Black Belt I spoke to recently (see today’s post) certainly sees no great distinction between the two. So now industry colleagues talk about “lean six sigma”, or even “lean sigma”.
In simple terms, six sigma originated in Motorola as a methodology for improving the quality of outputs, whereas lean was developed within Toyota as methodology for improving the efficiency of processes. For a review of these two approaches and explanation of how they have merged, you might try this website, which is designed for those “New to Lean Six Sigma” – albeit it does so from a six sigma perspective.