Executives in banks are usually signed into complex contracts which boil down to a bonus even if the bank loses, and a bigger bonus if it succeeds.
The argument is that bonus structures are needed to attract the right 'calibre' of executive, even when that patently fails to be the case.
I work at BT, and a couple of years ago, the Global section was the only part of the business to make a loss. The head - brought in about a year previously, was sacked, and his payoff would take me twenty-five years to earn! I wish I was that useless!