I think the reason why theirs so many busts is purely down to the scouts and scouting media.They relentlessly promote and overhype future busts from high school and their not objective.Alot of time it comes down to whether a player has 'that look of a football player'which means whites no matter how talented need not apply.They also do a good job of eliminating the competition so the Black players have no competition.But its competion that raises standards which makes worldwide sports like Futbol and boxing such compelling sports for the reason thast the best athletes around the world play.
Alot of the busts are good athletes ,have good to fairly productive college careers,their picked to play in the NFL from high school,given 5 star prospect status and coddled on campus,treated like VIPs and guaranteed to start.Their athletiscm enables them to put up good stats againt weaker college opposition.When their drafted thier given big contracts and though their still coddled,thier also expected to produce and the step up in class from more difficult play books and scemes,a more disciplined,regimated proffesional enviroment,competing against players that are more athletic,technically better and tactically more astute leaves many of the busts 'in over thier heads'
The good thing is that White players over the last few years in all positions cope better with that step up in class.It seems the defensive busts are given a shorter string.Epic 58 million bust Tyson Jackson was no longer starting throughout his second season,guys like Maybin and Gholston hardly play.Teams for the most part can cope with sub standard recievers if they have a good QB,running game etc.But if teams have defensive players that cant read a game,make tackles or pick up coverage the teams going to get thumped.