Re: "... the number of incidents dropped dramatically."
Jedit, the number of incidents that occurred out of hours dropped.
It was neither that they slacked off nor about actively faking incidents. What happened was, that they maintained the system at a certain level of instability where at one point an incident would occur, such as a predictable batch job abort (there was no proof of actively causing incidents though). After the incentives changed, they built more robust procedures and programs and also improved their monitoring system to get early warnings for predictable incidents.
Must have been a fun time though before. They got the huge extra pay and the praise ("the IT wizards saved the Bank. Again!")