One of the things that's changed in the draft over the years is nowadays, almost every talented kid plays a year at KY or NC or Duke, etc, and then goes into the draft lottery pool. Very few go four years of college. The result is a bunch of teenagers entering the NBA--most of whom lack the strength and maturity to play against NBA vets. As a result, the draft is a bigger crapshoot than ever. You just don't know what these skinny kids are going to look and play like in 2-3 years. And they certainly aren't going have much impact their first couple years in the League. If they do, it's the League coming down to their level. Something that's hard to notice.
It's a good argument to increase the age limit for the NBA, and force these kids to stay in school a couple more years, or even graduate.
[Looking at this post again, I'm trying to figure out why I put it here. It isn't a criticism of Brown, or a defense. Maybe it's Brown being so young he hasn't figured out what he wants to do yet in his life. I hope that doesn't mean he isn't totally committed to basketball.]