Lean Six Sigma: The Five Phases
Lean Six Sigma is an organizational principle that aims to constantly enhance the speed and quality of processes to satisfy the customer in a way that maximizes accuracy and flexibility while minimizing operational costs. It was first used by an American multinational telecommunications company in the late 1980s. A quality engineer known as Bill Smith created Lean Six Sigma as a way to improve quality and measurement systems with the end goal of eliminating errors. This was a stage in the telecoms company’s history when error rates were through the roof, creating too much rework, scrap and redundant testing that did not sit well with customers.
The Lean Six Sigma approach focuses on the identification and elimination of factors that lead to variations in the process. By taking out the variation, results of the process can be precisely predicted each time. With a system that puts these predictable results within a range of acceptable performance based on a customer’s perspective, the process can be free of errors.
Engineers in that telecoms company were not contented with that though. They have observed from experience that process changes do not always fix the problem from the root, which means many of such changes are ineffective. Additionally, the changes would not be reliable because operators would go right back to how they did it originally after a while. From such issues, the five phases of Lean Six Sigma were born.
In this phase, the parameters for the process are set, together with expectations for the process from a customer perspective. This is to make sure that any changes actually improve customer experience.
In this phase, the present performance of the process, product or service is measured to find out what is actually occurring, especially from a customer’s viewpoint. This step aims to make sure that the basis for analysis and solution are concrete and actual facts rather than theories or anecdotal data.
In this step, the source or sources of the variation are determined through analysis of the product or service using the derived measurements. This makes sure that the root cause of the problem is determined and not just the symptom.
This phase involves the creation as well as testing of possible solutions to the problem. The point is to make sure that the desired results are obtained and that variations are controlled or eradicated.
In this final phase, the changes are applied, all supporting systems are updated, and the process, product, or service is placed under control – usually statistical process control – to make sure that the solution is completely and sustainably implemented, and to help detect when performance begins to dip.