WEAKNESSES Average play strength and isn't as physical from press coverage as he could be. Might be knocked around by big NFL receivers if he's asked to press.
http://www.nfl.com/draft/2016/profiles/william-jackson iii?id=2555179
Posted this once before and this my be the concern in Joseph's defense.
This also..
Reason he'll fall in draft: Jackson is a gambler who can be beaten on double moves, and he's not an NFL-grade tackler yet. Plus, smaller, quicker receivers have given him fits, so he might be pigeonholed into a specific role in the NFL in a man-heavier scheme, which might eliminate a few teams, even if they feel they need a cornerback. Some clubs have high grades on him, but there's a wide range of opinions on Jackson in NFL circles.