If they see a QB that has what they determine to have starting QB qualities at some point in the not too distant future, I think it is very good draft capital to use. We all hope that Sam is our QB of the present and future if he is playing well. But a good young back-up is not only good insurance, he can be a good investment in the future. In that sense I agree with Alan.
At the same time, I agree that it is the time to win. If there is a player there that can really help you fill an immediate need now, then take him instead.
The thing I come back to is that once you get to the third round, most players are looked at for future potential, and not so much as rookie starters. So at that point, why not make that be the QB position?