I think a lot of people fall off the TDD wagon because of this exact thing—they learn TDD by working on new code and then can’t seem to apply it to their existing work projects. And then they give up, naturally! When this happens, I help the person focus on the difference between “test-first” and “test-driven”. I hope that this offers them more-realistic expectations regarding the outcome. With test-first, we focus on correct behavior and fix defects. Usually, but not always, when...
