Reminds me of an old story where a pizza place held a competition among the employees, to see which cashier could convince the most people to upgrade their medium pizzas to a large. The POS system was set to track whenever a medium was upgraded, and would award the cashier one point. The employee with the most points each week won something like free movie tickets.

Employees would put on their best salesmen pitches, trying to get customers to upgrade their medium orders to larges. But one cashier always won, pretty much without exception. He was going to see a new movie every week for free. And he didn’t even seem to be trying.

His trick was that whenever a customer ordered a large, he would just put it in as a medium and then immediately upgrade it. It gave him the point for the upgrade, with zero actual sales effort on his part. So every time he had a customer order a large, he got a point by default. Customer ordered three large pizzas? Three points. He didn’t even bother trying to convince people to upgrade their pizza sizes, because the free points from every large order were already enough to let him win every week.