This articles aims to de-mystify Six Sigma, not debunk it. It is a brilliant business management system to achieve major customer service improvement through quality assurance. As a business initiative, it has achieved great things for such industry leaders as American Express, Motorola, GE, Johnson and Johnson and the Starwood Hotels chain.

Why is it called Six Sigma?

Sigma is a Greek letter which, in statistical formulas, stands for standard deviation (Greek letters always make stats look more professional!). Standard deviation? That just describes how far a sample (such as a group of items) spreads out from the mean or average.

For example, suppose that someone were to record the ages of a thousand people in a shopping mall, and discovered that there was a goodly sprinkling (there’s a nice precise statistical term) from babies through to the very elderly, but a slight concentration in the 30-40 age bracket. If the figures were turned into a graph, they would see a high standard deviation from the mid-point age of 35, and the bell curve produced would look a little like a fried egg.

If, on the other hand, a graph were made of the ages of a thousand people who had joined the “I’m 35 today” club, all the sample would be bunched together with a very low standard deviation. The graph would resemble a pole. When the sample is 99.99966% alike, that’s Six Sigma. At only 30.85% alike, that’s One Sigma.

How are Six Sigma Statistics Applied to Business?

Stated simply, the company takes a customer satisfaction requirement, such as on-time delivery or no faulty goods or no billing mistakes – or perhaps its entire operation. It establishes Sigma Teams, conducts training, employs a Sigma Toolbox (that is, a range of given skills, techniques and statistical analysis) and works towards the goal of Six Sigma. That means improving the process, product or component under scrutiny until it is 99.99966% free of defect. The graph produced from Six Sigma results is an upright column – the phallic symbol every major corporation wants to boast.

99.99966% free of defect is a mighty ambitious goal, but worth striving for. Some companies find they are performing at 4 Sigma and are delighted to make it to 5 Sigma. Bear in mind that 4 Sigma still means 99.38 % accuracy. Isn’t that already excellent? What’s wrong with 99.38%? Sounds great as an exam mark!

Yet consider a company that sells 500,000 items (presumed free of defect) per month. At 4 Sigma (99.38% free of defect), some 3100 customers every month are thoroughly disgruntled with the shoddy goods they have received. That’s an awful lot of future sales in jeopardy, messy refunds, time wasted and items scrapped. The benefit of clear statistical analysis of all customer-oriented processes and products becomes apparent and is one of the great strengths of this management strategy.

The Six Sigma Black Belt

Every new strategic management process seems to generate its own jargon and buzz words. Six Sigma has devised Black Belts, Green Belts, On-Ramps, and DMAIC.

Of course, Black Belt is a nice macho term from the martial arts world. The person appointed as Black Belt will feel rather special and important ... which will help sweeten the pill of having to undergo a great deal of training, especially in statistical analysis. The Black Belt is, in other words, a team leader who has been removed from the normal workforce to concentrate on this role. A Green Belt often has a similar level of training but remains in his or her normal position and doubles as a DMAIC team member.

Six Sigma Black Belt Certification

The skills and management knowledge gained by undertaking training to become a Black Belt are recognised in the business world as having great value. Consequently, Six Sigma certification is something of a prize and can be an excellent career move.

The DMAIC Problem Solving Technique

This is standard fare for Six Sigma teams – the common process for all problem-solving. Groups of three to ten, under the leadership of a Black Belt or Green Belt, work through these steps:

• Define
• Measure
• Analyse
• Improve
• Control

Side Benefits of Applying This Great Process Management Strategy

Six Sigma may be aimed at better meeting customer needs and improving products and services, but the very operation of the process has many unexpected benefits. Team members acquire skills, exposure to senior management, an opportunity to shine, a new enthusiasm for their work, and a sense of achievement and pride. Key players such as Black Belts and Green Belts have all these benefits with the additional opportunity for accreditation. Managers at all levels gain clearer priorities, better teamwork from staff, improved time management, a developed team and data analysis skills for ongoing evaluation.

Who can benefit? Everyone. Being selected for Six Sigma training is a great opportunity, even if it feels threatening. Large corporations are crazy if they don’t apply it. Medium-size business can benefit, too, if they can set aside time and free up employees for the training and meetings. Costs vary with consultancy and training firms. It’s worth taking the time to investigate Six Sigma courses on the market.