For instance, Gapper says certain traits are shared by all notorious rogue traders: They’re perceived as outsiders in their white-shoe firms, and they compensate by being charismatic. They’re control freaks who have spent the formative parts of their careers in back-office jobs where trades are checked and settled. And they’re all very clever. The most mysterious flaw they share: When they have gambled themselves into such a deep hole that it is almost impossible for them to get out, they don’t stop. “They carry on until they are either caught or the loss rises to a disastrous level,” writes Gapper.

For instance, Gapper says certain traits are shared by all notorious rogue traders: They’re perceived as outsiders in their white-shoe firms, and they compensate by being charismatic. They’re control freaks who have spent the formative parts of their careers in back-office jobs where trades are checked and settled. And they’re all very clever. The most mysterious flaw they share: When they have gambled themselves into such a deep hole that it is almost impossible for them to get out, they don’t stop. “They carry on until they are either caught or the loss rises to a disastrous level,” writes Gapper.