But there are worthy challengers. I'm going to look at four candidates here - Hibbert, Joakim Noah, Dwight Howard, and DeAndre Jordan. (I thought long and hard about other guys, including Serge Ibaka, but ultimately I think these four stand above the rest based on a combination of individual and team success.)
Let's start with some data on one-on-one defense:
Of course, DPOY is (or at least should be) about more than just one-on-one field goal percentage. Next, let's look at how many minutes these guys are actually on the floor, and how they're doing on defensive rebounding (since an opponent's possession isn't over until you secure the ball).
Hmmm, tough times for Hibbert, and the real strength of Jordan's case. Dwight, Joakim and especially DeAndre all play significantly more minutes than Roy, and are all far better defensive rebounders. This is a bit tricky, because Hibbert's per-game rebounding totals are going to be affected by the presence of David West, Lance Stephenson, and Paul George, all of whom rebound at above-average clips for their positions. But the last chart above, based on SportVU data, shows that Hibbert also simply doesn't snare as many rebounds even when he's in prime position (within 3.5 feet of the rim). And his defensive rebounding rates have declined each of the past three seasons, even though West is playing fewer minutes himself this season.
Finally, let's look at team performance, both with these four on the court and off.
Yeah, Hibbert and Noah are awesome. They're both taking fantastic defenses to an entirely different level when they're on the court. I'm shocked by Jordan's stats here - the Clips don't exactly roll out stud defenders when DJ goes to the bench. Speaking of stud bench defenders, you have to take Dwight's position on this chart with a generous grain of salt because he's backed up by the superb Omer Asik. And he's often covering for three minus defenders around him, including James Harden, who went from Thanksgiving to St Patrick's Day without giving a single crap about defense.
So who should win the Defensive Player of the Year?
Man, is it tough to select one guy. Hibbert is the most dominant defender inside, and the lynchpin of the best overall defense. But he plays the fewest minutes and has really faltered on rebounding. Dwight is still a very good all-around defender, but he's not at the all-time level he set a few years ago in Orlando. And Jordan, while vastly improved in coverage and the league's undisputed best rebounder this year, still has inconsistencies at the rim and in pick-and-roll situations.
Which leaves us with Noah - the candidate with the fewest blemishes. He defends the entire court exceptionally well, he's been durable, and he's captained the second-best defense in the NBA even after losing ace perimeter defender Luol Deng mid-season.
Time to celebrate, Jo!
Data sources: NBA.com/stats, basketball-reference.com, Synergy Sports