Yes, but I can be assured that any input will follow one of the code paths that I explicitly wrote. There's no hidden runtime path that will bite me later, mean

Yes, but I can be assured that any input will follow one of the code paths that I explicitly wrote. There's no hidden runtime path that will bite me later, meaning that I had to at least reason about every non-happy path at some point in the dev process. It doesn't make the output "correct" but it's more likely to be correct than programming with happy-path-only optimism.