One of the great lessons of the last few years of quarterback drafting is the importance of knowing if your young quarterback is a finished product or a toolsy prospect in need of development. This is new, because for a very long time, toolsy prospects almost never worked out. It was kind of just Brett Favre for a bit there.
For the longest time, the best predictors of NFL success for a quarterback were two simple statistics: completion percentage and games started in college. As a general rule, good NFL quarterbacks were accurate college quarterbacks who showed that accuracy for multiple seasons, and exceptions were few and far between.