Memory hook: Build quality in; inspect outcomes; improve the system.
Must remember
Quality means meeting relevant requirements and fitness for intended use; grade describes a category or feature level. A basic product can be high quality. Prevention and appraisal are costs of conformance; internal/external failure are costs of nonconformance. Investing in prevention can reduce expensive rework and customer harm.
Quality assurance/process improvement asks whether the delivery process can produce suitable results; quality control examines outputs. Acceptance validates that authorized stakeholders accept the deliverable against criteria. Testing performed by the development team does not automatically constitute business acceptance.
Use cause-and-effect analysis to explore contributors, Pareto analysis to prioritize significant categories, control charts to study process variation, and checksheets to collect consistent observations. A process can be statistically stable yet consistently outside specification. Avoid changing a stable process after every random fluctuation without evidence.
Choose metrics that inform decisions: defects escaping to customers, lead/cycle time, throughput, rework and benefit adoption. Maintain accurate accessible artifacts and versioned decisions. A dashboard of green task statuses can conceal low product value or poor quality. Run retrospectives/lessons learned during delivery and assign improvement owners rather than waiting until the end.
Choose under exam pressure
| Requirement | Choice and reason |
|---|---|
| Repeated defects from one handoff | Investigate process causes and prevention. |
| Stable process still fails customer tolerance | Improve capability; stability alone is insufficient. |
| Need formal deliverable acceptance | Compare with agreed criteria and obtain authorized confirmation. |
Traps
- Quality is not the same as luxury or feature count.
- A lesson recorded but never acted on is not an improvement.
Active recall
1. Prevention versus appraisal?
Avoiding defects versus checking for them.
2. Internal versus external failure?
Defects found before customer delivery versus after.
3. Why use a control chart?
To understand variation and signals that a process may have changed.
4. Can a stable process be unacceptable?
Yes; it may consistently produce results outside required tolerances.
5. What makes a retrospective useful?
Specific improvements with ownership and follow-through.