XBTUSD funding rate is generally positive, i.e. more often than not, longs pay shorts, and stays in the 15-20% annualised band. However, it is also prone to violent moves, especially around big run-ups and sharp sell-offs. If you intend to hold a position in XBTUSDT for an extended period of time, funding can potentially eat significant part of your profits from price move. In such situations, you can get into a BitMex funding swap trade to convert the floating funding exposure to a fixed one.