We do go over this every year and I agree with the person who said that you just use common sense.  You're not going to purposely take a bust just because he's a need.  A BAP also makes little sense if the difference in value isn't significant.  Keep in mind that it is an educated guess more than an exact science.  With maybe an exception near the very top, I think of them more in ranges than a strict order.  For example, he's an "early fourth round pick" versus we have to take the 90th ranked player on our board over the 91st ranked player when the latter is a huge need and the former is not.  

I also highly question the value drops.  In the example of the 13th best player being available while picking 18th, I would ask why didn't the teams in spot 13, 14, 15, 16 or 17 pick him?  Most teams have multiple needs.  Are you really telling me that NONE of those teams had a need at that position?  Not likely.  Even if so, why didn't one of those teams draft him as BAP?  Remember, in order for a player to fall, you must have strictly need based drafting teams ahead of you.  Maybe the guy we think is 13th isn't as good as we think.  Are we confident that we are right and all of those teams are wrong?  Maybe we're the ones overlooking something.  Lastly, if we are confident that one player has clearly superior value and it isn't a need, then you trade down!  If he really is that much better value than the other options, some team with a need at that position will be desperate to trade into your spot.  If no one wants to trade to your spot, then again, you really have to question how good is the value.  Are you really giving up much with going with the need?

The goal is to win.  A draft pick doesn't help the team win if he's sitting the bench.  I know a starter can always have a season ending injury, but is that really playing the odds?  I also look at it from an improvement factor.  Let's say you can pick between a player with a score of 88 or another player with 87.  If you already have an 80 on the roster for the first player's position, that pick only helps you by 8 points.  If you have a 30 at the second position, that pick helps you by 57 points.  In this example, your team improves far more by passing the BAP and taking the need.

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