Cost of Poor Quality (COPQ)
topic
Cost of poor quality (COPQ) in ring spinning: internal failure costs (rework, re-coning, downgrade: 1–3% of revenue), external failure costs (customer claims, returns, reputation: 0.5–2% of revenue), appraisal costs (testing, inspection: 0.5–1.5%), and prevention costs (SPC, maintenance, training: 0.5–1%). Total COPQ typically 3–8% of yarn revenue. World-class mills achieve COPQ <2%. External failure cost is 3–5× more expensive than internal failure cost; both are 10–20× more expensive than prevention.
Role
COPQ analysis is the most persuasive tool for justifying quality improvement investment to financial management. Demonstrating that the mill's current COPQ is 6% of revenue — and that a $200,000 investment in SPC and maintenance would reduce it to 3%, saving $600,000/year — is an unambiguous financial argument. Building COPQ measurement and reduction into the mill's management system is the industrial application of quality engineering knowledge with the clearest financial return.