Definition
Planning, execution, inspection, and re-engineering cycles (also known as the wearing of the Rings) are important elements of strategic deployment control.
In detail
The PDCA Cycle (Plan-Do-Check-Adjust) is the core closed-loop follow-through of Policy Deployment control; it organizes improvement activities into four stages: first clarify the goal and plan (Plan), then implement on a small scale (Do), then evaluate the gap between results and the goal (Check), and finally adjust the plan or standardize based on the gap (Adjust). It addresses the problem of "improvement activities lacking systematicness and continuity," ensuring that every improvement can be verified and locked in. A Kaizen Event is itself a round of PDCA, just compressed into a 3—5 day sprint; PDCA as a control cadence can be stretched further to a monthly scale; compared with Policy Deployment, PDCA is a methodology at the execution level, while Policy Deployment provides the goal and resource framework. Typical outputs are: Action Plan, checklist, adjusted Standard Work, or new goals.
Example in practice
A factory's defect rate exceeded the standard for three consecutive months. The plant manager gathered the team to use the PDCA cycle: first, analyze data to identify main causes (Plan); pilot a new work method on one line (Do); after one week, compare defect rate data (Check); if effective, standardize the work and roll out to all lines (Act). The entire process lasted one month, ultimately reducing the defect rate, and the new standard was incorporated into daily management.