The most overlooked cost in perpetual contracts isn't the trading fee—it's the funding rate. The mechanism is simple: when there are too many longs, if you're holding a long position, you'll periodically pay shorts; when shorts are overcrowded, it works the other way around. Settlements happen every few hours, and while it doesn’t show up in your P&L, it’s constantly being deducted. The result? Even if you’ve got the direction right and avoided liquidation, your money might still slowly disappear—especially for those who chase a trend in a one-sided market and hold their position for too long. Before opening a position, check whether the funding rate is positive or negative, and how large the absolute value is. This step takes less than 10 seconds but determines whether your position will be "riding the wind" or "paying to stand guard." The crowded direction will always come with a cost.