PDCA(plan-do-check-adjust) is an iterative four-step management method used in business for the control and continuous improvement of processes and products.

Plan

Establish objectives and processes required to deliver the desired results.

Do

The do phase allows the plan from the previous step to be enacted. Small changes are usually tested, and data is gathered to see how effective the change is.

Check

During the check phase, the data and results gathered from the do phase are evaluated. Data is compared to the expected outcomes to see any similarities and differences. If the data is placed in a chart it can make it easier to see any trends if the PDCA cycle is conducted multiple times. This helps to see what changes work better than others, and if said changes can be improved as well.

Adjust

This adjust phase is where a process is improved. Records from the “do” and “check” phases help identify issues with the peocess. These issues may include problems, non-conformities, opportunities for improvement, inefficiencies and other issues that result in outcomes that are evidently less-than-optimal. Root causes of such issues are investigated, found and eliminated by modifying the process. Risk is re-evaluated. At the end of the actions in this phase, the process has better instructions, standards or goals. Planning for the next cycle can proceed with a better base-line. Work in the next do phase should not create recurrence of the identified issues.

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