質量成本 (COQ) 

A method of determining the costs incurred to ensure quality. Prevention and appraisal costs (cost of conformance) include costs for quality planning, quality control (QC), and quality assurance to ensure compliance to requirements (i.e., training, QC systems, etc.). Failure costs (cost of nonconformance)

include costs to rework products, components, or processes that are non-compliant, costs of warranty work and waste, and loss of reputation.