Unit tests is like buying insurance but you don’t know how much insurance has paid you if things go wrong. You spend a lot of time and effort to make your code

Unit tests is like buying insurance but you don’t know how much insurance has paid you if things go wrong. You spend a lot of time and effort to make your code testable, figure out what the useful test is and change the unit test when you do refactors in hope it speeds up your project, except you cannot really know if there was a net gain in speed/ reliability vs proper QA and other techniques