Maintenance margin
The maintenance margin is the minimum margin a futures exchange requires to keep a position open. When losses bring the margin down to it, the position is liquidated, which is why the real liquidation price sits a little closer to the entry than 1 / leverage.
The exchange sets it as a small percentage of the notional, and the percentage rises in tiers as the position gets bigger. The margin you put up to open a position is the initial margin; the maintenance margin is the floor under it. Your exchange shows the resulting liquidation price when you open the position.
Learn more: isolated vs cross margin and how to avoid liquidation.