Some don't understand what BPA really means. It has been argued on these forums and others many times over again. Some think BPA is Best player available. Period. This just simply isn't true and I will give an example. Lets say your the Buffalo Bills and you have the 15th pick. Your up and the best player available is a QB that should of gone at #3 but you already have your franchise QB and a darn good back up what do you do?
You try to trade back in the draft but no one wants to bite. Do you draft BPA or do you draft BPA at Need? What does BPA stand for? How many teams in our case would pick that QB? answer is no one.. so you look at your need list. We looking for CB, OT, Edge (examples) who is there at those positions? then you pick it.
The BPA is over used without true meaning.