In all types of business, industry or government organizations, decision-making is a vital part of the routine. Many of these decisions are very often based solely on intuition and/or experience. Six-Sigma minimizes the personal elements by quantifying the issues and using statistics to provide a means of determining probabilities of success and failure. Experience and tribal knowledge feed into the data gathering process and thus quantifiable validation is required prior to acceptance of decisions.
It is a structured, data driven approach that can be applied to any aspect of business. It is used to improve customer satisfaction, eliminate waste and increase profits. The premise is that where work is being done, waste is being generated. The higher the waste level, the greater chance of poor customer satisfaction, higher cycle times, increased defect rates and most importantly – profit loss.
The term “Six Sigma” is a statistical term that refers to 2 defects per billion opportunities (or 99.999998 percent accuracy), which is as close as anyone is likely to get to perfect. A defect can be anything from a faulty part, an incorrect customer bill, and excessive waiting time at a doctor’s clinic to potentially unsafe municipal drinking water. Most businesses with average quality of Three Sigma (99.73% of products and/or services within specification) are probably losing about 25% of their revenue due to costs of poor quality. As the conformance level increases, the revenue that would have gone into prevention and inspection becomes available for other uses in the business.
The following table presents a comparison between Three Sigma and Six Sigma Performance
![]() | Six Sigma speaks the language of business. It specifically address the concept of making the business as profitable as possible. |
![]() | In Six Sigma, quality is not pursued independently from business goals. Time and resources are notspent improving something that is not a lever for improving customer satisfaction. |
![]() | Six Sigma uses an infrastructure of highly trained employees from many sectors of the company (not just the quality Department). These employees are typically viewed as internal charge agents. |
![]() | Six Sigma raises the expectation from 3-sigma performance (99.73% accuracy) to 6-sigma 0r 99.999998% accuracy. |
![]() | Guaranteed minimum five times return on investment within a year if deployed properly. |
Black Belts are the heart and soul of the Six Sigma quality initiative. Typically the “best of the best,” their main purpose is to lead projects and work full time until they are complete. They work on chronic issues that are negatively impacting the company’s performance. As a general rule of thumb, one to two percent of a company’s workforce will be a BB. BB is 4 weeks classroom training or 2 weeks on top of the GB training.
Green Belts are employees trained in Six Sigma who spend a portion of their time completing projects, but maintain their regular work role and responsibilities. Depending on their workload, they can spend anywhere from 10% to 30% of their time on their project(s). GB is 2 weeks classroom training with a 6-8 weeks gap between each week of classroom training for applying the tools learnt in first session.
Typically employees trained in the basic Six Sigma tool that participates on project teams. Supports the goals of the project, typically in the context of their existing responsibilities. YB is one-day classroom training.