Ten ways a check passes while the thing it checks is broken

# Summary Checks and automated tests can pass while the systems they monitor are actually broken. The article catalogs ten ways this happens—including checks that are incapable of failing, checks written for the wrong technical format, and checks that examine easy-to-access parts of code rather than where users actually encounter problems. The key insight is that re-running the same check doesn't catch these failures; testing *differently* is what exposes them.