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A green test result is reassuring when developing high-quality software. The code compiled, the tests executed, and the assertions passed. For C and C++ development teams, these results provide an important measure of progress and confidence in software behavior.

For teams developing safety-critical and highly regulated software, however, passing tests are only part of the verification challenge. A successful test can demonstrate that a software component behaved as expected under a specific set of conditions, but it doesn’t necessarily show how thoroughly the implementation was exercised, whether critical failure scenarios were evaluated, which requirements were verified, or whether sufficient evidence exists to support a safety assessment or compliance audit.