What 1000x leverage means
The number is real, the survivable holding period is not. Worked through with live data.
What the number literally means
At 1000x, $100 of stake controls $100,000 of exposure. Every 0.01% the market moves is $10, or 10% of your stake. The liquidation distance at a 5 basis point maintenance rate is 0.05%.
The position is finished before it opens
Costs are charged on exposure. At 16 basis points round trip, 1000x costs 160% of the stake to open and close. There is no price path that recovers that, because the fee is larger than the money you put up. On this fee schedule the position becomes unrecoverable somewhere around 625x, and every rung above that is worse.
How long it survives in practice
On Zcash the one-minute series moves further than the entire 1000x liquidation distance in 72.5% of individual minute bars. On S&P 500 ETF that figure is 3.2%. The honest description of a 1000x position is not a trade; it is a bet on the next few price ticks, priced worse than a coin flip.
Why anyone offers it
The headline multiplier is a marketing number, and a cheap one. Positions at that rung close almost immediately, pay a fee on the way in and another on the way out, and almost never stay open long enough to be a real liability for the venue. It is the loudest number on the page precisely because it costs the least to print.
The useful version of this
If the appeal is a large outcome from a small stake, the multiplier is the wrong lever, because above a few hundred x the fee alone decides the result. Open the calculator, set the multiplier where the round-trip cost stays under a few percent of the stake, and read the liquidation distance against that market's normal daily range. That is the range where the price actually determines the outcome.