A Chief00 response: "A casual fan can only appreciate a limited number of parameters which contribute to on court success."
A BigErn response: "There are a lot of tools who contribute to the Boneyard."
Serious response: Court awareness (peripheral vision, quick assessment of moving parts), understanding opponents strengths and weaknesses (which opposing players are excellent offensive rebounders and how they create to get rebounds such as physically establish presence under the boards or come from further out), flexibility in response to ball being shot to anticipate a rebound for a missed shot (that is when to box out, when to leak, when to block, when to go for the rebound), timing and ability to see caroms; These factors are just as important if not more important in a players ability to rebound than just leaping ability, size or strength.
As examples: Shabazz lacked the physical attributes but was excellent at rebounding. One of the biggest factors in the first NC imo was Rip's ability to understand when he was needed for defensive rebounds and when he could leak for fast breaks. He constantly kept opposing teams off balance. Neither of these two players had the physical attribute of Brimah's height, but Brimah was never able to sublimate many of the aspects that factor into rebounding.