[jjeaff]

The customers aren't to blame, but it's a little unfair to blame Robin Hood for what amounted to a black swan event. One of the main reasons they ran out of capital in this case was not because of the volume of trading, it was because of the one sidedness of the trades (lots of buys) and all being on one stock. RH's margin requirements skyrocketed because so much of their liability was concentrated in one stock. Risk (and this margin requirements) go up the more the risk is focused into a single point of failure.