What is the key purpose of the 'Control' phase in the DMAIC cycle?

The key purpose of the 'Control' phase in the DMAIC (Define, Measure, Analyze, Improve, Control) cycle is to ensure that the improvements made during the project are sustained over time. This phase focuses on implementing control systems to monitor the processes and performance metrics established in previous phases, allowing for ongoing oversight of the changes that have been made.

By developing control plans, standard operating procedures, and training for staff, teams can maintain the gains achieved through process improvements. This ensures that any process improvements do not regress and that the benefits realized are not temporary. Regular monitoring and control mechanisms allow organizations to respond promptly to any variations or deviations from the desired process performance.

In contrast, identifying root causes belongs to the Analyze phase, defining project scope is part of the Define phase, and analyzing variance is typically conducted during the Measure or Analyze phases. Each of these earlier phases contributes to the overall improvement process but does not encompass the primary goal of the Control phase, which is to secure ongoing success and stability in the improved processes.