My take is that the job involves taking risks with amounts of money that would make most normal folk a nervous wreck. So it attracts those who naturally ignore possible disastrous consequences and with apparent nerves of steel, gamble with the pot. If they get into trouble the same personality will feel less concerned about hiding the problem until they have solved it with a large win, and which point they're back in the game again.
Sure, huge wins and subsequent bonuses for not creating wealth for the world but simply attracting it, is the norm. But it is a wafer thin difference between choosing the wining "investment" and buying into a loser. Just saying that in my opinion that environment attracts a certain type who will be more likely to get into such trouble, but will not be investigated if they happen to be successful.