I don't know if I necessarily agree with this. I'm not necessarily coming at this from the question OP proposed, but from an interviewing standpoint. I've seen a lot of interview questions that didn't necessarily have a real use in reality, so asking the interview _why_ they wanted something implemented can be seen as badgering them and like you might not be a good fit. On the other-hand, if you were to focus your questioning on the implementation, and the interview was fishing for you to question _why_ they wanted something, you may be seen as an someone with a propensity to over-engineer. It's potentially a lose/lose situation.