[neilknowsbest]

To add a little more detail, ES is the e-mini S&P 500 futures contract traded on the CME. The way it works is that you put up some amount of money called the "margin", and you get to buy or sell a larger "notional" valued contract. The difference between the margin that you put up and the greater notional value is the implicit leverage that parent comment refers to.

You can find the contract specs on the CME's website here [0]. The implicit leverage is actually a bit greater than the parent comment says. The contract notional value is defined as $50 x Index Value, which is currently around 6500. So the contract represents close to $325,000 and the exchange's margin requirement is around $21,000. Interactive Brokers seems to require similar margin [1]. The margin requirement is around 6.5% of the notional value, i.e. 15x leverage. So a 6.5% decrease in the S&P 500 would wipe out the account.

Not sure why the parent comment is downvoted, I suppose it has a moralizing tone?

[0] - https://www.cmegroup.com/markets/equities/sp/e-mini-sandp500...

[1] - https://www.interactivebrokers.com/en/trading/margin-futures...