I forgot who, but someone semi-famous said unit tests should be called "programmer tests". That is, unit tests are for the programmers, not for verification. Th

I forgot who, but someone semi-famous said unit tests should be called "programmer tests". That is, unit tests are for the programmers, not for verification. They are used as a tool by the programmer to: Tighten up the development loop (manual e2e is often too slow) Prove to yourself that the code does what you want Communicate intent to other programmers Documentation to other programmers Help programmers debug regressions I really think this holds up because, really, who except for programmers that can read and comprehend unit tests are going to trust they verify a product works? The more distant a stakeholder is from a project the more holistic the testing needs to be in order for that stakeholder to trust it.