The mantra of Six Sigma training is to restrict your focus to only one or two activities that are responsible for more than 50% of defects. To narrow down your focus you can use the Pareto chart, which is a very powerful tool for this purpose.

The Pareto chart is based on the 80-20 rule, which says that 20% of the business is responsible for 80% of problems. It is sometimes also called the 4 to 50 rule, on the basis that a mere 4% of business is responsible for more than 50% of its problems.

The Pareto Chart

The Pareto chart is the outcome of the studies of the early twentieth century Italian economist Vilfredo Pareto on wealth distribution in different countries. His studies made him conclude that a small percentage of about 20% of people controlled the major part of a society’s wealth - to the tune of nearly 80%. Similar distributions have been observed in other areas, and are termed the Pareto effect. 

The Pareto effect works for quality improvement, as 80% of the problems stem from just 20% of causes.  The Pareto chart is structured to depict the Pareto principle in action. The chart is designed to arrange relevant data in such a way that the small percentage of vital factors causing the bulk of problems is automatically revealed.

Concentrating efforts to improve these few identified ‘problem causing’ areas will have an enormous overall positive impact including quality. It will also be extremely cost effective as compared to efforts for improvement lacking specific focus.

Purpose

One of the main purposes of the Pareto chart is to focus on one of the identified activities at a time to optimize results. Once the first is set right, the focus can shift to another activity. It is crucial to select the right team for implementation of corrective measures.

This is a very difficult exercise; however, it remains extremely important. If you select a team before you narrow down your focus, you may end up with the wrong team because they will not know what to solve. Consequently, there will be no consensus on what really needs to be done.

Six Sigma envisages applying statistical tools for getting variation out of a process. 'Sigma', the eighteenth letter of the Greek alphabet, is a measurement describing a standard deviation on a bell curve.

A higher sigma represents fewer defects being measured. Six Sigma training, which denotes world class quality, signifies a scant 3.4 defects per million opportunities. However, this is a tall order - and the fact remains that even top companies operate in the range of 3 sigma (i.e. nearly 60,000 defects per million opportunities).

The crux of Six Sigma training is quality and speed. The way to go about achieving it is to first make sure that you have the Pareto charts of different elements that are major contributors to problems. Then conduct root cause analysis meetings with your in-house experts on each element, taking care not to combine them, but treat each element separately.

This will help companies to find and fix many undetected root causes - and to achieve dramatic defect rate and cost reductions.