Leverage is a division, not a setting
The multiple your exchange lets you select is a cap, not a description. What you are actually running is position value ÷ margin. Choose 20× on the venue but only commit half the margin the position needs and you are at 10×; commit a quarter and you are at 40×. The number that matters is the one the arithmetic gives, not the one in the dropdown.
The line worth reading twice
"A 1% move against you costs X% of margin" is the whole of leverage in one sentence. At 10× a 1% move costs 10% of your margin. At 25× it costs a quarter of it. At 50× a 2% wobble — an ordinary hour in crypto — takes the position.
That is also why the liquidation gap shrinks faster than intuition suggests. At 10× you have roughly 9.5% of room; at 20× about 4.5%; at 50× about 1.5%. Doubling leverage more than halves your margin for error, because the maintenance requirement is subtracted from an ever-smaller starting cushion.