What are heuristic methods for ending testing?

Heuristic methods for ending testing are approaches based on experience, intuition, and informal rules that help determine when the testing process can be considered complete, even when full exhaustive testing is not possible.

Examples of heuristic methods:

• 80/20 Rule (Pareto Principle): 80% of defects are found in 20% of modules or functions. Testing can be considered complete when these critical areas are sufficiently tested.
• Defect density metric: Testing ends when the number of defects found per test unit (e.g., per 100 test cases) decreases to an acceptable level or becomes zero over a certain period.
• Test coverage status: Testing can be considered finished when a certain percentage of code, requirements, or functionality (e.g., 95%) is covered. However, this is only an indicator, not an end goal.
• Build stability: Testing ends when the last few builds do not contain new critical defects or have a minimal number of low-priority defects.
• Exit criteria compliance: Formal criteria defined at the initial stages of testing (e.g., "all test cases from the critical set are passed, with no critical or blocking defects"). Although formal, defining these criteria often involves heuristics.
• Team experience: The decision to conclude is based on the collective experience and understanding of risks by the testing team and other stakeholders.
• Time and resource constraints: Testing may be stopped when allocated time or resources run out. This is a forced heuristic based on business realities.
• Stakeholder satisfaction: If stakeholders are satisfied with the current quality and are ready to accept the product, testing can be concluded.

These methods are used alongside more formal metrics and reports to make an informed decision about the product's readiness for release. It is important to understand that they do not guarantee the absence of defects but rather help assess an acceptable level of risk.