I agree w/ who mentioned shooting as becoming paramount.
However, that doesn't explain the other point that I'm about to make.
NBA scouts had enough film on Harrell to point to his weaknesses clearly. He's played 3 yrs on a pretty big stage.
There is footage of what he does well which is cool, but there is also tape on what he doesn't or can't do at a high level (shooting the 3, for ex).
A few players went ahead of him that didn't produce as much data. I.E. - it's yet to be clear what they don't do well. More than likely, they dont do a lot of things well,there just isn't enough tape out there to confirm it. They have length measurables, are a couple years younger, and "potential".
The idea of potential is really simply a substitute for describing a player as an unknown quantity.
It's kind of a lazy way to go about evaluation. Instead of focusing on what attributes and skillsets exist w/ a proven commodity, instead they shift the focus on what the more experienced player doesn't do well. In turn, scouts point to a fraudulent concept referred to as potential in regards to explaining why they are selecting a younger far less proven commodity.
Everybody knew Lebron and Kobe were headed for greatness, there was enough film on them w/o seeing them @ the Collegiate level. Guys like Kwame Brown didn't get the same buzz though, much more risk there.
Scouts/GMs prefer to go w/ the risk/reward angle more times than not. For a guy like Looney or McCullough to go ahead of Harrell, it certainly wasn't a "you get what you earn" pecking order.
Sure, the NBA has produced draft picks at a young age that have fit the potential criteria. There's also been examples of potential going untapped.
Maybe the scouts will end up being right here. Success tends to boil down to a lot of things out of a player's control. How crowded is the roster? Does the coach have his job on the line? Does upper mgt prefer our guy, or do they like a few of their other guys @ the same position already on the team more?