Well, then by that definition you are not refactoring either, and in fact nobody is refactoring. Because any change can unintentionally change the behavior. Tha

Well, then by that definition you are not refactoring either, and in fact nobody is refactoring. Because any change can unintentionally change the behavior. That's what we call a bug, and them bugs don't care about your definition. And Unit tests alone cannot ensure that the non-happy-paths are functional.