There is a history of disappointment and failure using Six Sigma methods, as there is also a history of success.
Many individual projects fail. Worse yet, many efforts at process improvement are abandoned due to difficulties with Six Sigma.
There are any number of books and consultants happy to sell you a way to make Six Sigma last: perhaps it’s simply not meant to last, not in the way many want. Much of that disappointment derives from unrealistic expectations.
Six Sigma is a rigorous process improvement method used to reduce variation within a narrowly specified project. It’s based on a five-step method, with a specific set of tools and statistical methods or tests proposed for each step. At the conclusion of each step, a review is done before proceeding. Projects are tied to specific financial gains. They are done under the aegis of a ‘champion’ who serves as a facilitator and provides organizational tie-in to the executive suite. The methods of project management are employed throughout to keep things on track.
When done with care and wisdom, a Six Sigma project will yield valid and reliable results. The organization will know specifically the amount of confidence they can invest in the results and the interval in which that confidence resides. Learning will have occurred. The solution to the particular problem will have been tested and can be relied upon to some very specific limits.
Six Sigma projects are led by a highly trained specialist. These specialists are called ‘belts’, and they come in various colors. There is a hierarchy of belts, with the master black belts on top. The nomenclature is borrowed from the martial arts.
When one project is done, these specialists move on to another project. There is status and reward involved with being a belt. It’s even become sexy within the world of quality management to be a belt, or as sexy as anything within our world gets.
What’s not to like about a methodology that delivers reliable results?
That sounds like the answer to all our problems. It isn’t. As good as Six Sigma is at reducing variation in a narrowly focused effort, using project management, that very rigor is limiting. By its nature and structure, there are things that Six Sigma cannot do for you.
All work is done is a system of inter-related processes. That is the truth. Work is done is systems, and it’s done over time. Generally, within those systems, it matters what order the work proceeds in; there is most often a linear flow from one process to the next. Hand-offs from one process to the next are defined by the output/input model, and the output of the upstream process needs to fall within the specifications of the process downstream. Then, within that system and those processes, the work is done by people and the system itself is managed by people.
While Six Sigma can help improve the quality of the output by way of variation reduction, it’s not so good when applied to the system itself. The interactions of the processes, over time, are not easily grasped by Six Sigma methods. Six Sigma doesn’t address flow issues well. Nor can Six Sigma be used as a management method: you might reduce the variation of your management outcomes, but there is little to guide you in choosing either the methods or the outcomes.
Finally, the use of specialists is limiting: work is done by people. It would be better to have the people doing the work responsible for the quality of their output.
Six Sigma does its work very well, indeed. It cannot by itself transform your system or organization. It’s not fair to Six Sigma, its practitioners, or the organization to expect it to do what it cannot.
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Paul Deuth, a Six Sigma black belt, has worked in quality management for 12 years and holds the position of media director with the American Society of Quality’s Hartford section. Reach Deuth via www.eyeqsolutions.net or learn more through the group’s website at www.asqhartford.com .
