Cost of Poor Quality: An Event-Based Calculation Worksheet

Calculate the cost of poor quality by linking each internal or external failure cost to a defect event. Keep prevention and routine appraisal separate, reconcile recoveries, and avoid charging the same material or working hour twice.

A rejection entry may show the value of ten scrapped parts. The same defect can also generate sorting, rework, extra inspection and a return shipment. The quality lead needs one event record; finance needs evidence that those costs are distinct.

Agree what enters the COPQ total

ASQ’s cost-of-quality framework separates prevention, appraisal, internal failure and external failure. COPQ concerns the failure costs. Internal failures are found before delivery; external failures reach the customer.

Routine inspection and prevention training belong in the wider cost-of-quality view. Extra sorting required because a defect occurred belongs against that event under the accounting policy you agree. Keep the classification consistent so a rising training budget is not presented as deteriorating quality.

Calculate one event without duplicated costs

Illustrative scenario: event Q-026 affects a machined component lot. The values below are invented to demonstrate the worksheet. The scrap unit cost already includes the material and processing cost of each scrapped part.

Gross recorded failure cost is ₹7,580. If finance confirms a ₹300 scrap recovery, net recorded cost is ₹7,280. Keep the recovery as a separate linked line. Do not add the material value of the ten scrapped parts again, and do not count the six rework hours in both the labour and a loaded machine-hour charge that already includes labour.

This total excludes an unverified estimate of lost sales. Record lost production hours separately until finance agrees a valuation method. A machine stopped for an hour does not automatically mean an hour of saleable output or a lost customer order.

Build the event record across departments

Start the record when quality confirms a failure requiring extra work. Give it a defect ID, product, lot or serial scope, detection date and internal/external classification. Production records extra time and affected quantities. Stores supplies the issue, return and scrap references. Customer service records the complaint and shipment references. Finance validates rates and recovery entries.

Each line needs an owner, source document, quantity, unit, rate, amount, cost category and status: estimated, confirmed or disputed. Preserve the original estimate when a later invoice replaces it; mark which version enters the current total. Where two departments submit the same invoice, one line carries the cost and the other links to it.

Review open costs before closing the event

Quality and finance jointly review the event after disposition. Their acceptance checks are practical: all cost lines have evidence or an explicit estimate label; duplicate document references are resolved; affected quantities agree with the disposition record; and recoveries have their own dates and evidence.

An unsettled freight claim keeps that line open. It need not hide the confirmed subtotal. If one invoice covers several defects, document the allocation basis and make the allocated amounts sum to the invoice. When a returned part is repaired and shipped again, distinguish the original failure cost from ordinary production for unrelated orders.

For the next review, group confirmed events by defect and process. Compare like periods and product mixes. A large one-off customer return should remain visible rather than disappear into an unexplained average. Give the selected corrective action an owner and check whether that same failure repeats.

Connect quality work and cost evidence in Optiwise

Our production entries, configurable QC forms and repair/rework flow provide the operating records behind the review. With Optiwise’s no-code modules, relations and formulas, you can configure an event ledger and aggregate its approved lines. The classifications and valuation rules remain the ones your quality and finance owners approve.

COPQ worksheet questions

Should normal inspection be counted as COPQ?

Routine appraisal is a separate cost-of-quality category. Identify extra inspection caused by a failure and apply the agreed policy consistently.

Can we include customer compensation before it is agreed?

Keep it as a labelled estimate or disputed line with an owner. Show confirmed and estimated totals separately so an unresolved amount does not look settled.

Review one defect event with us and map the production, quality and cost records needed to close it.