1. PRs should target development, which is an *unstable* branch, so no biggie if something breaks
2. CI should catch things like syntax errors, failing tests, or poor test coverage
3. I trust my colleagues to do their work properly and fix things if they've made a mistake
What do you mean "doesn't run"? Tests should catch the most obvious/common bugs. If you mean it doesn't compile, then something is wrong because why would any engineer check in code that doesn't compile unless they're distracted or under pressure? And again, this would be caught by CI.