{ "schema_version": "core-reviewed-term-ai-handoff-v1", "version": "core-reviewed-term-ai-handoff-v1", "contract_status": "preview", "distribution": "per_term_read_only_ai_handoff", "no_write_operations": true, "canonical": { "url": "https://core.yogoq.com/en-US/core/cost-of-poor-quality", "slug": "cost-of-poor-quality", "locale": "en-US" }, "summary": { "schema_version": "core-reviewed-term-summary-v1", "term_id": "a1c09438-5ded-5ece-acb4-a7f7c2c166bc", "canonical_slug": "cost-of-poor-quality", "canonical_url": "https://core.yogoq.com/en-US/core/cost-of-poor-quality", "locale": "en-US", "display_name": "Cost of Poor Quality", "english_name": null, "abbreviation": "COPQ", "short_definition": "Cost of poor quality is the economic loss from defects, rework, returns, warranty claims, churn, and missed opportunities caused by quality failures.", "quality": "reviewed", "publication_status": "published_reviewed", "version": "core-reviewed-term-summary-v1", "last_reviewed_at": "2026-05-14T00:00:00.000Z", "sources_count": 2, "limitations_key": "core-trust-policy-v1-2026-06-22" }, "content": { "definition": { "key": "definition", "title": "一言でいうと", "text": "Cost of poor quality is the economic loss from defects, rework, returns, warranty claims, churn, and missed opportunities caused by quality failures.", "items": [] }, "formula": { "key": "formula", "title": "計算の考え方", "text": "COPQ = internal failure cost + external failure cost + rework + returns/warranty/credits + quality-driven opportunity loss. Formula | COPQ = internal failure cost + external failure cost + rework + returns/warranty/credits + quality-driven opportunity loss. | Use it as the primary operating calculation Bridge | Beginning COPQ + defect increase - prevention impact - detection improvement +/- demand and mix change = revised COPQ | Use it to explain changes between reviews Segment | Split by customer, product, channel, and period | Use it to find deterioration hidden by averages", "items": [ "Formula | COPQ = internal failure cost + external failure cost + rework + returns/warranty/credits + quality-driven opportunity loss. | Use it as the primary operating calculation", "Bridge | Beginning COPQ + defect increase - prevention impact - detection improvement +/- demand and mix change = revised COPQ | Use it to explain changes between reviews", "Segment | Split by customer, product, channel, and period | Use it to find deterioration hidden by averages" ] }, "boundary": { "key": "boundary", "title": "含めるもの / 含めないもの", "text": "This metric is comparable only when inclusion and exclusion rules stay stable. Include | Scrap, rework, returns, warranty, credits, complaint handling, quality-driven lost sales | They reflect economic impact Exclude | Normal prevention, inspection investment, necessary redundancy, training | These are investments in quality, not failure cost Define explicitly | Brand damage, churn, reputation risk | Estimation rules must be stable", "items": [ "Include | Scrap, rework, returns, warranty, credits, complaint handling, quality-driven lost sales | They reflect economic impact", "Exclude | Normal prevention, inspection investment, necessary redundancy, training | These are investments in quality, not failure cost", "Define explicitly | Brand damage, churn, reputation risk | Estimation rules must be stable" ] }, "usage": [ { "key": "meaning", "title": "意味", "text": "Cost of poor quality, or COPQ, turns quality problems into a decision metric. It includes internal failure, external failure, rework, customer remediation, and estimated opportunity loss so teams can prioritize process improvement and service design with economic evidence.", "items": [] }, { "key": "usage", "title": "役立つ場面", "text": "Use Cost of Poor Quality to decide prioritizing quality investments because it highlights defect rate and the inspection cost versus failure cost tradeoff. It changes prioritization by forcing teams to state the horizon, boundary conditions, and controllable drivers. It informs adjustments when rework time or customer impact shift, so decisions stay grounded in current conditions.", "items": [ "Use Cost of Poor Quality to decide prioritizing quality investments because it highlights defect rate and the inspection cost versus failure cost tradeoff.", "It changes prioritization by forcing teams to state the horizon, boundary conditions, and controllable drivers.", "It informs adjustments when rework time or customer impact shift, so decisions stay grounded in current conditions." ] }, { "key": "usage", "title": "使い方のポイント", "text": null, "items": [ "Define the unit and horizon before comparing defect rate across options.", "Keep the primary driver separate from secondary noise and one-off shocks.", "Document data sources, estimation steps, and confidence ranges for review.", "Translate the tradeoff into thresholds that can be monitored over time.", "Revisit assumptions when the market boundary or policy setting changes." ] }, { "key": "drivers", "title": "何が数字を動かすか", "text": "Breaking the metric into drivers clarifies what action should follow the review. Defect rate | More defects increase scrap and rework Detection timing | Customer-discovered failures cost more than internal catches Process variation | Weak standardization increases repeat work", "items": [ "Defect rate | More defects increase scrap and rework", "Detection timing | Customer-discovered failures cost more than internal catches", "Process variation | Weak standardization increases repeat work" ] } ], "misunderstandings": [ { "key": "misunderstandings", "title": "判断するときの注意点", "text": "Do not decide from the number alone; align assumptions, period, segments, and companion metrics. Tracking only easy returns understates lost sales and reputation risk. More inspection alone can delay prevention work. Using COPQ for blame reduces reporting quality.", "items": [ "Tracking only easy returns understates lost sales and reputation risk.", "More inspection alone can delay prevention work.", "Using COPQ for blame reduces reporting quality." ] }, { "key": "misunderstandings", "title": "よくある誤解 / 落とし穴", "text": null, "items": [ "Cost of Poor Quality is not a universal rule; results depend on boundary assumptions and data quality.", "A single metric like defect rate is not sufficient without considering rework time and customer impact.", "Short term movements can mislead when responses happen with lags." ] } ], "examples": [ { "key": "examples", "title": "最小例", "text": "A service team sees 20 returns, 80 hours of rework, and $3,000 in credits each month. Root-cause review shows most failures start in onboarding setup. Adding an automated check cuts rework in half, which makes the quality investment visible in financial terms. After the review, the owner did not treat the metric in isolation. They compared it with companion metrics, checked segment differences, documented assumption changes, and verified data quality before changing the plan. Whether the number improved or deteriorated, the team identified the driver, assigned an owner, and fed the learning into the next budget, operating review, or experiment cycle.", "items": [] } ], "comparisons": [ { "key": "comparisons", "title": "似ている言葉との違い", "text": "Quality management cost | Prevention and appraisal investment | COPQ is failure loss Customer support cost | Service effort | COPQ isolates quality-driven support Revenue loss | Churn or lost sales | COPQ counts the quality-caused portion", "items": [ "Quality management cost | Prevention and appraisal investment | COPQ is failure loss", "Customer support cost | Service effort | COPQ isolates quality-driven support", "Revenue loss | Churn or lost sales | COPQ counts the quality-caused portion" ] }, { "key": "related_metrics", "title": "一緒に見る指標", "text": "Companion metrics turn a good-or-bad reading into a discussion of causes and actions. Operational Efficiency | Waste and rework | COPQ reduction improves efficiency Process Improvement | Root-cause removal | Shows where to intervene Service Quality Calibration | Expected service level | Reduces external failure", "items": [ "Operational Efficiency | Waste and rework | COPQ reduction improves efficiency", "Process Improvement | Root-cause removal | Shows where to intervene", "Service Quality Calibration | Expected service level | Reduces external failure" ] } ], "faq": [ { "question": "Is COPQ only accounting cost?", "answer": "No. It can include estimated churn, lost sales, and reputation impact if the estimation rule is documented." }, { "question": "Is inspection cost COPQ?", "answer": "Usually no. Inspection is appraisal cost; COPQ is the cost of failures." }, { "question": "Should small defects be tracked?", "answer": "Yes when they are frequent. Small repeated rework often becomes material." } ] }, "sources": { "source_refs": [ "concept:business-concept-0084:en-US", "concept:business-concept-0084:ja-JP", "concept:business-concept-0144:en-US", "concept:business-concept-0144:ja-JP", "manual_merge_map:next-exact-duplicates-2026-04-28" ], "visible_sources": [ { "label": "OpenStax: Principles of Management", "url": "https://openstax.org/details/books/principles-management", "kind": "Tier-S open textbook" }, { "label": "Wikipedia: Quality costs", "url": "https://en.wikipedia.org/wiki/Quality_costs", "kind": "Supplemental reference" } ] }, "related_terms": [ { "topic_id": "1dfab88f-8126-57f8-aa70-e11e8cc4b8ab", "canonical_slug": "service-quality-calibration", "canonical_url": "https://core.yogoq.com/en-US/core/service-quality-calibration", "title": "Service Quality Calibration", "relation_type": "used_together" }, { "topic_id": "99f8864b-7bc8-5751-b0d1-40161ad0dee7", "canonical_slug": "operational-efficiency", "canonical_url": "https://core.yogoq.com/en-US/core/operational-efficiency", "title": "Operational Efficiency", "relation_type": "related" }, { "topic_id": "ed9364f3-d42d-552f-bf81-674b1f0d1528", "canonical_slug": "process-improvement", "canonical_url": "https://core.yogoq.com/en-US/core/process-improvement", "title": "Process Improvement", "relation_type": "related" } ], "quality": { "quality": "reviewed", "publication_status": "published_reviewed", "source_count": 2, "last_reviewed_at": "2026-05-14T00:00:00.000Z", "trust_policy_version": "core-trust-policy-v1-2026-06-22" }, "limitations": { "policy_version": "core-trust-policy-v1-2026-06-22", "professional_advice_boundary": "reference_only_not_professional_advice", "text": "This page is reference information for research and learning. For accounting, legal, finance, health, security, or other individual decisions, confirm against primary sources or qualified professionals.", "items": [ "Public pages support general understanding and practical context; they are not professional advice for individual cases.", "Fast-changing information such as regulations, accounting standards, prices, product specs, and legal requirements should be checked against primary sources before final decisions.", "Even when AI-assisted drafting or audit is used, publication relies on quality gates and human-readable evidence." ] } }