PDCA (Plan-Do-Check-Act) is an improvement cycle based on the scientific method of proposing a change in a process, implementing the change, measuring the results, and taking appropriate action to get better result. It was developed by W. Edwards Deming as the Japanese Concept in the 1950s.
The PDCA cycle has four stages:
Plan: Setting goals for a process
Do: Implement the changes
Check: Evaluate the performance results
Act: Adjust and Standardize to stabilize the change
When the result does not meet our expectation, we must begin the cycle again starting from Planning.