This is true, but you still go through a painful process of learning what that actually means. My early sins included happily relying on field injection in Spr

This is true, but you still go through a painful process of learning what that actually means. My early sins included happily relying on field injection in Spring (don't), happily blasting stuff into Ruby objects (don't), mocking my software's world into an unrecognisable comic book universe of gravity-defying nonsense (don't) and so on. A common criticism of TDD is that poor tests make things harder to change, not easier, and I believe it, because I have absolutely done that.