I was taught that you should solve the problem first, and then write the code. TDD doesn't change that; it forces you to at least define the problem before you

I was taught that you should solve the problem first, and then write the code. TDD doesn't change that; it forces you to at least define the problem before you take a stab at writing the code. Of course, as you delve deeper into the problem, you often learn something that changes your understanding of the problem. That's where the third step of TDD comes in - refactor. TDD doesn't make people reluctant to refactor their code; it forces them to do it. Refactoring is a vital part of TDD.