Why Have Belts in Lean and Six Sigma?

Motorola and the General Electric company made the greatest contributions to introduce Six Sigma across business in the 20th century. The deployment of Six Sigma often relied on “belts” of various colors, people who completed a course of study, delivered one or more projects using the methodology, and took an exam to be certified practitioners, teachers and project leaders. Six Sigma was made popular and formalized few years before Lean. One could argue that Lean has yet to formalize a similar certification regiment. Because of this many organizations adopt the belt training and certification as a way to move their Lean and Six Sigma efforts forward. Opinion remains divided among the Lean community, however, on whether Black Belts and Green Belts are necessary and desirable.

For the past 20 years, customers and business partners have asked me about a “Lean certification” similar to the Six Sigma belt. I have always balked at this because the Lean body of knowledge seems to me to be too broad to learn, practice, test and be certified in, within a timeframe that customers would consider reasonable. Six Sigma is a widely applicable problem solving methodology that does not specify operating system building blocks, work management methods or countermeasures per se. Lean does include these things, and is open-ended, adapting and growing. Most people grasp that they don’t really need a “Lean certification” covering the entire body of knowledge. They need just enough to get started, to get managers to a common level of understanding, or to get to the next level. These days it is quite common to find yellow, green and black belts programs in Lean and/or Lean Six Sigma that are built from problem solving methods and specific tools selected to fit an organization’s needs.

Why not have belts in Lean? The belt certification approach earns a bad reputation when organizations decide that belts will be the main people responsible for doing continuous improvement and building the lean management system. This approach goes against several of the very central ideas of Lean, namely valuing people as individuals, engaging them in creative problem solving, and that it is everyone’s job to build, maintain and improve the system.

Another common objection to belts from parts of the Lean community is the “Toyota doesn’t have Black Belts” argument. This is true. However, Toyota doesn’t have lots of things. They don’t have kaizen events. They don’t have value stream managers. They don’t have 5S (it’s 4S). They don’t have Lean. Where do we draw the line? If the adapted practice or learning approach works in the non-Toyota context, why not keep using it? Further, if we were to follow the “Toyota doesn’t so we won’t” approach, would we not also need to do whatever they did as part of their Lean system? These may include the suggestion system, jishuken, TQM, a no-layoff policy, rotating jobs every 2 hours, and a management vocabulary that uses more than a skosh of Japanese words. All good ideas, but only in the right context.

Sometimes people say developing and certifying Lean belts is unnecessary because “We made all of these improvements using only X,” with X being a small subset of Lean methods. This X may be just 5S and kaizen suggestions, only kanban and daily huddles, only Toyota Kata, or just value stream mapping and A3 problem solving. More power to those for whom this is true. What could be better than being able to forever resolve all of problems using only a few commonsense methods? These are the fortunate few who never face complex challenges beyond their current level of knowledge. In the reality that I am familiar with, this approach works great until it no longer does.

A common question that all organizations ask sooner or later is, “Where do we look for the next improvement?” Answers can be found in a variety of ways including visiting and benchmarking with other companies, hiring external gurus, going to Lean conferences to network and compare, and deepening knowledge and insight into Lean and Six Sigma by investing in the education of in-house expertise. Even Toyota has had an internal group of experts working on getting better at TPS, called the Operations Management Consulting Division, for more than 40 years. Organizations need the equivalents of Black Belts who are familiar with the various tools and methods, know how to assess a situation, and can organize a project to apply a set of proven practices to improve a situation. Black Belt certification is not the only approach to developing this expertise, but specialized education and practice tends to develop expertise, regardless of field.

When belts are collected mainly to mark completion of a required management training, or just as a status symbol, they don’t fulfill the basic function of a belt. That is to avoid being caught with our pants down. Whether Black Belt or by another name, smart organizations use a Lean and Six Sigma education process to maintain and upgrade the improvement-related skills of their staff via learning and application. Smarter organizations move the majority of their Black Belts into operational and leadership roles, where they can both lead based on Lean and Six Sigma philosophies and develop this culture within their team.

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