Posted Tuesday, Oct. 16, 2012, at 2:43 PM
David Romer has shown pretty conclusively that NFL coaches are far too conservative in their fourth down play-calling ("Do Firms Maximize? Evidence from Professional Football"). Could something similar be happening in the NBA with turnovers and offensive rebounds? That's one suggestion in Zach Lowe's piece on NBA trends:
Nobody seems to care about offensive rebounds anymore. Teams in the 1980s and early 1990s used to rebound about one-third of their own misses, but the league-wide offensive rebounding rate is down nearly 25 percent these days and threatens to reach a new historic low every season. That's in part because of the 3-point shot, which has redistributed shot attempts away from the rim area, where easy offensive rebound chances are born.
But it also reflects a growing conservatism that has swept much of the league. The Spurs, Magic (under Stan Van Gundy), and Celtics are among the teams that essentially forfeit offensive rebounds to run everyone back on defense and prevent fast breaks. This philosophy sometimes goes hand-in-hand with a near prohibition on gambling for steals in favor of staying in front of offensive players and forcing mid-range shots. The two ideas don't always go together, with personnel often dictating how coaches approach these questions. The Lakers, for instance, forced fewer turnovers per possession than any team in history — conservative! — but pounded the offensive glass hard with Pau Gasol and Andrew Bynum. The Mike Brown Cavaliers had a similar tendency to play conservatively everywhere but on the offensive glass.
Back to Romer, the causal explanation of excessively conservative playcalling is essentially the same as what John Maynard Keynes wrote about why banks fail:
A sound banker, alas, is not one who foresees danger and avoids it, but one who, when he is ruined, is ruined in a conventional way along with his fellows, so that no one can really blame him.
If you bet on housing when everyone bets on housing, then when everyone's bets go bad it's just a "nobody could have predicted" kind of situation. If you bet against housing when everyone bets on housing, then when you lose money you're fired. Same with coaches. Nobody gets fired for calling for a punt in a situation when every other coach would punt, even if all the coaches are wrong.
It's not clear to me that the NBA has a comparable dynamic around crashing the boards. Arguably, the very same increased three point shooting that's decreased the number of offensive rebound opportunities has also increased the costs of giving up the fast break. On the other hand, I do see some evidence that offensive rebounding is unduly discounted. If you see someone who scores extremely efficiently in part because of a lot of dunks after offensive rebounds, people often feel the need to qualify it by saying "well it's all putbacks" as if somehow that's an illegitimate way to score.