And was promptly removed from the game.
I really think he just rubs Coughlin the wrong way. Knowing next to nothing about his personality, only seeing his potential, I leave him in there and let him work it out. In the NFL you have to know when to hold 'em, and know when to fold 'em... and this kid has always had the best hand at the table, he doesn't know what it is to have to fold. Hence lots of effort-related fumbles, ala Ricky Watters.
The Giants lost 6 straight games anyway... as little as Wilson was on the field during that period, the team would have been no worse off though that period with him getting a feature back's workload. And would have been better off going forward, with a more confident, experienced player at runningback. This of course being a hypothetical world in which 1) Wilson doesn't get injured, and 2) he isn't (apparently) an immature little prick whom the head coach cannot stand.