And the best QB ever (sorry to say as a Saints fan) was taken in the 6th round.
At the end of the day, it is a position where to be among the best requires not just the physical tools, as all positions in the NFL do (a grade A arm), but also insane drive/competitiveness and near genius level mental processing speed - you have to get your pre-snap read right, and you have about 1.5 seconds after the snap to figure out whether that pre-snap read was correct, or was some sort of disguised coverage, and figure out where to go with the ball.