The Good Ol', "you never looked at that before, why are you looking at it now?". Yeah, I've gotten that one too. Well, the answer could be several reasons:
1. Through discussions/research you realize this is an area that recently has been scrutinized by examiners, when in the past maybe they have not paid much attention to it, i.e. Flood insurance.
2. You have a better understanding of how the control fits into the big picture and you feel it warrants review.
3. Due to an incident in the recent times, this control warrants greater scrutiny, i.e. teller embezzeled money, maybe we need to look at our controls a bit better.
4. If it was a regulatory requirement, maybe it was amended recently and it is required to be reviewed.
5. Last but not least, "Because I said so!". (Thats my personal favorite!

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