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. In the late 1980s, an American multinational telecoms company became its first user. 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 occurred at a time when the telecoms company dealt with too much rework, repetitive testing, and scrap, leading to customer dissatisfaction.
Identifying and eliminating process variations is the main function of the Lean Six Sigma framework. When the variation is out of the picture, the outcome of the process can be correctly predicted every single time. When a system is designed to ensure that such a predictable outcome remains within an extent of acceptability from a customer’s point of view, process errors can be obviated.
But that was not the end for engineers in that telecoms company. Their experience told them that a lot of process changes were ineffective because they did not reach the root of the problem. Additionally, the changes would not be reliable because operators would go right back to how they did it originally after a while. These exact issues soon led to the five phases of Lean Six Sigma.
In this initial phase, the limits for the process are laid down, along with customer expectations for the said process. This is to make sure that any changes actually improve customer experience.
Here, the ongoing performance of the process, product or service is measured in order see what exactly is happening, especially in the eyes of a customer. 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 ensures that the origin of the problem, not just a symptom, is known.
This phase entails studying possible changes to the process, product or service as well as testing them. The point is to make sure that the desired results are obtained and that variations are controlled or eradicated.
This phase consists of the application of changes, upgrade of supporting systems, and control – generally statistical process control – of the process, product, or service to ensure full and sustainable implementation and ensure timely identification of signs of declining performance.