DMAIC lifecycle and phase gates

Learning objectives

• State the purpose of each DMAIC phase.
• List the deliverables required at each tollgate.
• Explain how tollgate governance prevents premature solutions.

The five gates

• Define — scope the customer problem and authorize the project.
• Measure — validate measurement and establish baseline.
• Analyze — confirm root causes with evidence.
• Improve — develop, pilot and select solutions.
• Control — sustain the result and hand over ownership.

Garment-factory example

A high-rework project cannot jump to retraining. The team must first define the defect, validate inspection agreement, establish DHU and confirm causal factors before choosing a solution.

Method

1. Agree exit criteria for each gate up front.
2. Bring documented evidence to every review.
3. Only proceed when the sponsor and process owner accept the deliverables.

Common mistakes

• Using DMAIC as a document checklist.
• Choosing a solution during Define.