Quote from lescor:
I guess first of all, we should be clear on how we're defining prop firms in this discussion, because it's a common source of confusion. There are two models. In the first, the firm rigorously screens potential candidates and hires them as employees, trains them in the house's specific methods and gives them a lot of rope. In this scenario, I could see guys being down 6 figures and still in business, because the plan was always to use house money and the bosses have confidence in their guys and their methods.
The second, and more common, business model is where the trader puts up capital and is basically opening a retail trading account on steroids. You get too low on your capital and you will get a call to deposit more funds. An overnight position blows up and you are net negative, it's put up cash or bye-bye. Sometimes the firm will let you go negative, for sure. They like you, you have a good record, do big volume, etc. The firm's model is to collect commission, and do it in a low risk manner. If they have confidence you can pull yourself out of trouble and keep churning volume, they will keep you alive, because they are making cash off you the whole time. But it's an exception, not a matter of course.
But 90% of the firm's accounts under water? No way. Simply because at prop firm's, like all traders in general, a large number are losing or making very little and their records don't warrant taking a risk on them.