In production management activities, for example, the production plan (Plan) is developed first, and production activities (Do) are carried out in accordance with the plan. In the production plan process, not only the production volume is determined, but also production staff, production methods and materials, as well as quality, costs and delivery time (implicitly when necessary). “Plan-Do-Check-Act cycle”

According to the concept of the PDCA cycle, actions are not simply carried out in accordance with the plan, but the Check (evaluation) and Act (improvement) activities are also carried out.

The PDCA cycle can be defined by the principle of actions on business activities. The PDCA cycle is considered to increase the number of management man-hours required. In particular, operations for collecting various historical data may increase the workload.

The Check (evaluation) step is sometimes called Study, leading to the name PDSA cycle. The process is also known as the Plan-Do-See cycle (the PDS cycle). In this case, See represents both Check and Act.