9.2.1—Quality control and assurance

Quality control inspects or tests outputs to find defects. Quality assurance designs systems, training and processes so quality is built in and monitored throughout production.

Control can catch a problem before delivery; assurance may prevent repeated problems and improve consistency. Both have cost and require a definition of quality.

A bakery can test finished weight (control) and standardise recipes, calibration and staff training (assurance).

Passing a test does not prove customers value the product, and quality is not only the absence of defects.