Defect Prevention
Defect prevention is the practice of reducing the introduction of defects by improving development processes, tools, and engineering practices.
“The measures that reduce the likelihood of recurrence of defects in work products and limit the propagation of defects in subsequent work products.”
(Definition reproduced from the ISTQB Glossary. Copyright belongs to ISTQB.)
View the complete ISTQB GlossaryWhat is Defect Prevention?
Rather than focusing only on detecting defects, defect prevention identifies root causes and implements improvements that reduce future defects.
Root cause analysis: Teams investigate why defects occur.
Process improvement: Coding standards, reviews, and training reduce defect introduction.
Long-term benefits: Preventing defects is usually less expensive than fixing them later.
Real World Example
A hospital medication system shows a different dosage warning in test than the one specified by the clinical safety rule.
The team needs precise language to separate what was observed, what should have happened, and whether the difference represents a reportable issue. Defect prevention provides that distinction.
The tester records the steps, data, observed behavior, expected behavior, and evidence so triage can focus on patient safety impact instead of vague descriptions.
The issue is handled faster because Defect prevention helps everyone discuss the problem using a shared testing vocabulary.
Practice Questions
Question 1
Which statement BEST describes Defect prevention in the context of ISTQB terminology?
Question 2
A tester needs to explain Defect prevention to a non‑technical stakeholder. Which approach is MOST appropriate?
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