I am frequently asked questions about Six Sigma as relating to quality processes and business management strategies and practices. So I wanted to share a book which I think explains the basics of Six Sigma clearly (and painlessly). Six Sigma is often viewed as a complicated and intimidating subject, so the author has chosen not to write a how-to book, but rather an introduction to this management strategy. Chowdhury’s book is written as a parable and tells of how Six Sigma helped transform the manner in which one fictitious company operates.
To start, together the number six and the sigma, the Greek letter, represent a statistical measure and a management philosophy which is focused on eliminating mistakes, waste, and rework.
The state of a manufacturing process can be described by a sigma rating indicating its yield, or the percentage of defect-free products it produces. A six sigma process is one in which 99.99966% of the products manufactured are statistically expected to be free of defects (merely 3.4 defects per million. At Two Sigma you’re making over 30,000 mistakes per million opportunities!). Sigma is like a measurement, used to determine how good or bad the performance of a process is, and it denotes the amount of variation within a process such that the higher the Sigma rating, the lower the variation. And the goal is to reduce the amount of variation (mistakes) in a repetitive process as much as possible.
Chowdhury uses a football analogy to explain that there are two ways to win games: making more spectacular plays (long passes, big runs, great interceptions) or by making fewer mistakes (penalties, fumbles, interceptions). Similarly, he writes, "Good companies focus on not making mistakes: not wasting time or materials, not making errors in production or service delivery, not getting sloppy in doing what they do best." He believes that although not as flashy as a big acquisition or exciting product launch (the "big play" in football), preventing mistakes can make you just as much money. And it gives you a discipline, structure, and a foundation for solid decision making based on simple statistics.
In attempting to improve a process, you need to know where you are and have a goal of where you want to be. Chowdhury writes that "Trying to improve something without having a numerical goal is like trying to lose weight without having a scale." Six Sigma provides the tools and methodologies to measure what is occurring, determine what to fix, and know when you’ve actually fixed it. However, the goal of Six Sigma is not simply to improve quality for the sake of improving quality, but to make customers happier and add money to the bottom line. Thus input from customers is critical to help the business understand what customers want, and don’t want.
Unique, clearly defined roles are an important part of Six Sigma; including "Black Belts" who lead and run the projects as well as the "Green Belts" who are the Black Belts’ support staff. Of course, the chance for success is limited unless the senior leaders of the company are bought in and active in the process, so they are termed the "Champions" of the Six Sigma projects. They provide commitment, funding, and inspiration to the organization regarding Six Sigma. They also often pick, evaluate and support the Black Belts in tackling their projects.
Special training is typically required for Black Belts and Green Belts in the five main points of the Six Sigma strategy: how to Define, Measure, Analyze, Improve, and Control the processes that produce increased customer satisfaction, company savings, and a healthier bottom line. Six Sigma forces you to clearly define the problem and your target so that you have a better chance of hitting it. It forces you to prioritize and focus on the problems with the greatest potential savings and positive impact. It also provides a methodology to challenge the status quo so that simply saying "Hey, we’ve done it this way for 10 years" is not a good enough answer. Six Sigma helps with the big questions that need to be answered, such as why the errors are being committed (from the Measure and Analyze phases) and how to fix them (from the Improve and Control phases, where you lock in your successes).
There’s plenty more to Six Sigma, but in summary you Define the problem, Measure where you stand, Analyze where the problem starts, Improve the situation, and Control the new process to confirm that it’s fixed – DMAIC.
Back in the day, Jack Welch, former CEO of General Electric, called Six Sigma "The most important initiative GE has ever undertaken." As someone who spent 18 years at GE and attained Green Belt status, I can attest to the benefits of utilizing Six Sigma on a variety of business processes and challenges. If you’d like to learn more about how Six Sigma can help your business, give me a call.
And remember: Without target dates (deadlines) it just doesn’t get done. If the IRS said, ‘Hey, just get your taxes in when it’s convenient for you,’ what do you think would happen?