Eddie Dekel points out the following puzzling fact.  At the gym most people wipe down the exercise machines and benches after they use them and not before.  There are a few obvious social benefits of this policy.  For one, you know better than your successor where the towel is most advantageously deployed.  Also, the sooner that stuff is removed, the better.

But still it’s a puzzle from the point of view of dynamic efficiency.  With this system everyone mops once.  But there exists a welfare improving re-allocation where one guy doesn’t mop and after him everyone mops before using the machine.  Nobody’s worse off and that one guy is better off.  A Pareto improvement.

In fact the ex-post-mop regime is especially unstable because that one guy has a private incentive to trigger the re-allocation.  He’s the one who saves effort.  So from an abstract point of view this is indeed a puzzle.   Moreover, there is this Seinfeldian insight that complicates things even further.

ELAINE: Never mind that, look at the signal I just got.

GEORGE: Signal? What signal?

ELAINE: Lookit. He knew I was gonna use the machine next, he didn’t wipe his sweat off. That’s a gesture of intimacy.

GEORGE: I’ll tell you what that is – that’s a violation of club rules. Now I got him! And you’re my witness!

ELAINE: Listen, George! Listen! He knew what he was doing, this was a signal.

GEORGE: A guy leaves a puddle of sweat, that’s a signal?

ELAINE: Yeah! It’s a social thing.

GEORGE: What if he left you a used Kleenex, what’s that, a valentine?

(conversations with Asher, Ron, Juuso and Eddie.  I take all the blame.)