Generated tests often mirror the implementation instead of the requirement, so a polished suite and high coverage can still provide weak protection.
Shared mistake: Code and assertions can encode the same wrong interpretation.
Weak signal: Tautologies, excessive mocks, and snapshots may never detect realistic faults.
Missing risk: Boundaries, invalid input, permissions, and failure paths are easy to omit.
False confidence: Tests may pass even after the behavior they claim to protect is broken.
Start expected outcomes from an independent specification. Review assertions, add integration coverage at important boundaries, and use mutation testing where its cost is justified.
Rewriting in plainer words…
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