What it does
Builds a Cost of Quality model splitting prevention / appraisal / internal-failure / external-failure costs, estimates the cost of poor quality from defect/incident data, computes automation one-time vs recurring cost vs saving with a payback period and break-even, and makes a prioritized investment business case. Uses real figures only, labeling missing inputs as placeholders.
When to use it
For QA economics and business cases — justifying or sizing the QA budget. Advisory; flag for human/finance review before budget decisions.
Prerequisites
qa.config.yml recommended (risk tiers, tooling, environments, process.release_cadence, gates); proceeds with stated assumptions if missing. Reads defect/incident/automation baseline signals.
Output
Test-economics / value-of-testing input to the 29119-3 Organizational Test Strategy / Policy / Test Plan (not itself a 29119-3 document) -> <paths.docs_dir>/COST-OF-QUALITY-<scope>.md.
Mechanics
How it works
- List assumptions and data completeness first; label each input actual/estimated/(placeholder)
- Build the CoQ model: prevention/appraisal/internal-failure/external-failure as ranges
- Estimate cost of poor quality from defect/incident data over the period
- Compute automation ROI: one-time vs recurring cost vs saving
- Derive payback period and break-even with the cycle assumption stated
- Make a prioritized business case tied to CoQ categories and expected reductions
Why it works
The theory behind it
Value of testing & test economics (CTAL-TM), grounded in the cost-of-defects/shift-left rationale (Principle 3): defects get exponentially more expensive the later they are caught, which funds prevention. Costs are ranges with stated confidence (Principle 1 — a cost model is a forecast, not an audited statement).
CTAL-TM · CTFL v4.0 §1 (cost of defects)
Example
See it in use
> /qa:cost-of-quality "2026 automation programme"✓ Correct when It splits prevention/appraisal/failure costs and shows automation ROI/payback with the cycle assumption stated.