It's that time in the football season when fans ask, "Whatever happened to...?"Whether because of injury, getting keyed on or avoided by the opponent, or just plain bad luck, some Big Ten players haven't been able to build on or repeat the big seasons they had in 2015.Here's a look at some of them:OFFENSE Illinois RB Ke'Shawn Vaughn rushed for a team-high 723 yards with six touchdowns and was projected to be the featured back this season.