If we strike your first sentence, "The worse the developer, the more tests he'll write", then I can mostly agree with you. It sounds like you have never worked

If we strike your first sentence, "The worse the developer, the more tests he'll write", then I can mostly agree with you. It sounds like you have never worked on a project with no tests and those same developers that write "write long-winded, poorly abstracted, weird code that is prone to breaking". A test suite doesn't eliminate bad code or bad coders, but it does give the better people on the team a handle to grab them by.