Tests are great as long as there's a strict discipline (you usually need to enforce this with tooling) of never committing a change that causes any tests to fai

Tests are great as long as there's a strict discipline (you usually need to enforce this with tooling) of never committing a change that causes any tests to fail. Then anyone who writes a test has to make it pass, and anyone who makes a change that breaks a test has to fix it. No rotting tests that passed long ago and have been failing for months that everyone ignores because whatever