Chapter 1 – Fundamentals of Testing
Failure – ISTQB Definition
Last Updated: July 12, 2026 · SoftwareTestPilot QA Team
Official ISTQB Definition
An event in which a component or system does not perform a required function within specified limits.
In simple words
The visible symptom — the app crashed, the calculation was wrong, the button did nothing.
Exam tip
Not every defect causes a failure, and failures can also come from environmental conditions, not just defects.
Related terms
- DefectA flaw in the product — code, requirement, or design — that could cause a failure when executed.
- SeverityHow bad the bug is technically — does it crash the app, corrupt data, or just misalign a label?
- VerificationAre we building the product right? — checking that the work product matches its specification.
Practice this term in the ISTQB Mock Test
40 CTFL v4.0 questions, 60-minute timer, instant scoring and chapter-wise breakdown.
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