cost of quality

**Cost of quality** is the **complete economics of quality including both preventive investment and failure-related losses** - it balances what an organization spends to avoid defects against what it pays when defects escape. **What Is Cost of quality?** - **Definition**: COQ equals prevention plus appraisal plus internal failure plus external failure costs. - **Good Quality Costs**: Prevention and appraisal are proactive spending to control process outcomes. - **Poor Quality Costs**: Internal and external failures represent losses from quality breakdown. - **Optimization Goal**: Shift spending toward prevention to reduce total COQ over time. **Why Cost of quality Matters** - **Strategic Planning**: COQ shows whether current quality spending mix is sustainable and efficient. - **Tradeoff Clarity**: Helps teams justify early investment that avoids larger downstream losses. - **Benchmarking**: COQ as percent of revenue enables maturity comparison across plants or business units. - **Risk Management**: High external-failure share signals elevated brand and liability risk. - **Improvement Direction**: Balanced COQ trend indicates whether quality system is moving from reactive to preventive. **How It Is Used in Practice** - **Category Standardization**: Use one COQ taxonomy and chart of accounts across all sites. - **Quarterly Review**: Track category shifts and tie major movements to process or product events. - **Portfolio Actions**: Fund prevention projects with highest expected COQ reduction per dollar. Cost of quality is **the management framework that links technical quality work to economic outcomes** - best-in-class operations lower total COQ by preventing failures early.