Back in the day, Chinese gold spot exchanges enforced daily forced liquidation and settlement, with long and short positions paying deferred fees to each other. The exchanges didn't directly collect this money, but when retail investors held a large long position and leveraged highly, the deferred fees became the platform's most stable, hidden source of income—retail investors paid long-term, and the platform indirectly benefited through trading volume and liquidity. The same applies to Bitcoin spot platforms now: They primarily rely on perpetual contracts(not pure spot trading), with long and short positions settling **funding rates** every 8 hours. When long positions are in the majority, they pay short positions; retail investors holding long positions for a long time are constantly paying. The exchange itself doesn't directly collect this money, but it greatly increases trading activity and open interest, indirectly generating transaction fees, liquidity, and user stickiness, indirectly becoming a large and stable source of income for the platform. The only difference is the terminology: back then it was called "deferred fees," now it's called "funding rates," but the essence is exactly the same。