How does Six Sigma DMAIC Process work?

DMAIC stands for Define, Measure, Analyze, Improve and Control. Each phase contributes to improving the process and reducing variation. The diagram illustrates how a team can narrow a broad list of possible inputs to the critical inputs supported by evidence; candidates are not established root causes merely because they appear on the list.

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Six Sigma DMAIC Process

In this illustration, Define begins with all candidate X’s, the possible inputs discussed in the previous section. Measure narrows them to a first hit list of 10–15, Analyze screens that list to 8–10, Improve focuses on 4–8 critical X’s, and Control sustains control of 3–6. These counts illustrate progressive focus; they are not required numbers or fixed phase gates. Analyze establishes causes using evidence, Improve tests solutions, and Control sustains the gains. Controlling the influential inputs can improve the project output Y.

Characteristics of a successful project:

• Should be related to your day to day work
• Should be manageable in terms of time-frame
• Should be aligned with business goals and results
• Should preferably address only one CTQ (Critical To Quality) parameter
• Should address issues which are important to the customer
• The improvements that you do should be locally actionable

CTQ stands for Critical to Quality: a characteristic that matters to the customer and can be expressed through a measurable requirement. Related characteristics may be described as CTD (Critical to Delivery) or CTP (Critical to Process). Examples include cycle time, quality scores and yield percentage, with a clear definition and an appropriate target or specification.

Projects must be tightly bound and must not focus on solving broad issue such as global warming or world’s pollution.

When a Six Sigma project is initiated, it generally happens that we do not scope the project appropriately. During the course of the project, we keep adding additional parts to the project and the team has to manage these additional items which were not considered earlier. This phenomenon of including additions to the project is termed as “scope creep” and leads to challenges in project execution at a later stage. Projects which lead to scope creep are termed as projects which are trying to solve “global warming”. In order for the projects to achieve the desired results, they must be tightly bound and must not focus on solving broad issues.

A process-focused business constantly realigns processes to remain capable of meeting changing market demands. Only by gaining predictability can an enterprise truly maintain capable processes to changing customer demands.

Here, we should focus on getting the Voice of Process to understand the real nuances that it may face during the course of its operations. Voice of Process helps in understanding the metrics and the inherent fluctuations of these metrics. Three key terms that help us define process capability are:

• Process Baseline
• Process Entitlement
• Process Benchmark

Six Sigma facilitates in understanding variation in our business processes!

Let’s understand the three key terms:

Process Baseline:
A process baseline describes its current performance over a defined period under the conditions actually experienced. It can include the average performance level and its variation. Long-term performance is assessed across an appropriate period and range of operating conditions; it does not require every input to be unconstrained.

Process Entitlement:
Process entitlement describes the best-case performance expected from the current process design under favorable, controlled conditions. It is often discussed in terms of short-term capability, with the process appropriately centered and important inputs controlled. Define the study conditions and sampling period: short-term performance is not a measurement at one instant.

Process Benchmark:
A process benchmark is a comparison standard, often the best known performance achieved by a comparable process. Researching the strongest results in the industry helps set an improvement goal. A benchmark is evidence of what has been achieved, rather than proof of the absolute best performance possible.