You look at arm strength and durability first. Stats are PR. 

 

ARM STRENGTH - When I see a quarterback, I look for the elite arm strength traits first. The easiest way to put it is the prospective quarterback must throw with the authority of a major league third baseman. Third basemen possess quick release, have velocity on their throw, and excellent touch on their throw so that its easy to catch. It takes time to turn the ball around and send it on it's way with mustard on it. Superior arm strength is a must.

 

Naturally strong arms don't have a lot of hang-time on deep throws. The elite throw has arc, but doesn't hang in the air the way it does with passers that must heave-ho to cover greater distances. 

 

DURABILITY - After arm strength, the most important elite trait to look for is durability. Height, weight and physical fitness combined are essential to play quarterback, but durability can be more of personal challenge than the result of poor measurements. Durability isn't determined by mobility, elusiveness, or running ability. The stronger the body the more durability it has. The propensity for injury to a quarterback is always an issue. The more durable the quarterback is, the less frequent quarterback injury interrupts the team. The quarterback must be able to function despite injury.

 

If these two things aren't clear up front, the likelihood the prospect will reach elite status isn't so good.

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