The NFL draft isn't so much an inexact science as it is a gamble. Teams spend countless hours researching potential prospects, hoping to figure out if they'll be successful at the pro level. However, there is simply no way to tell with 100 percent certainty how a player will handle himself as a professional or perform on an NFL field.
Even the most promising prospects can peter out, and a strong pro start guarantees nothing. Remember, Blake Bortles passed for 4,428 yards and 35 touchdowns in his second season. The best we can hope to do before the draft is make educated guesses as to which players could be busts.