The Five Phases of Lean Six Sigma
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. In the late 1980s, an American multinational telecoms company became its first user. The main motivation behind Lean Six Sigma, as created by a quality engineer named Bill Smith, was to improve the quality and measurement systems so as to prevent errors. This occurred at a time when the telecoms company dealt with too much rework, repetitive testing, and scrap, leading to customer dissatisfaction.
The Lean Six Sigma methodology mainly aims to point out and remove process variations. 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.
However, engineers at the telecoms company did not stop there. From their experience, they knew that several process changes did not address the root cause of the issue and were thus ineffective. Also, the changes would not work for the long term, with operators eventually reverting back to the original manner. From such issues, the five phases of Lean Six Sigma were born.
In this initial phase, the limits for the process are laid down, along with customer expectations for the said process. The objective is to guarantee improvement instead of degradation of customer experience with every change.
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. The purpose is to ensure that actual performance, instead of anecdotal or theoretical information, is used for analysis and finding a solution.
This phase involves identifying problem-causing variations by analyzing the product or service using the data measured. This ensures that the origin of the problem, not just a symptom, is known.
In this phase, potential solutions to the problem are designed and then tested. The purpose is to ensure that the intended effects are achieved and that variations are reduced, if not completely eliminated.
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.