This is a pretty interesting excerpt from the article based on pretty in depth analysis
"[The author] concluded that big men like Okafor tend to remain in the negatives in terms of defensive impact," Nick wrote. "[He] also noted that Okafor's best-case scenario is about average defensive production. The first development that needs to happen with Okafor would be an increase in effort if he is to become passable on defense."
"However, I'm a little wary about that happening," Nick continued. "Brett Brown gets his guys to play their tails off. Jah is a clear outlier in that regard."
Nick then moved to Okafor's rebounding to finish his scouting report. Okafor has deep-seated issues rebounding to, and they "revolve around poor and poor technique" according to Nick.
He cited my piece from February that concluded that Okafor's rebounding vis-a-vis his rookie peers was concerningly low. While his raw, per game rebounding totals look strong, the better statistic that determines what percentage of available rebounds he corrals sold him far short of future All-Star and All NBA players.