Plan, Do, Check, Act: the iterative four-step model behind continual improvement in every ISO management system.
The PDCA cycle is the engine of continual improvement. Plan sets objectives and the processes to reach them. Do implements those processes. Check measures results against objectives. Act corrects gaps and feeds lessons back into the next cycle.
ISO management system standards are built around this loop, which is why activities such as risk assessment, internal audit, and management review repeat on a regular schedule rather than happening once.
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