I set a stop-loss, so why was the actual execution price still quite a bit worse than the set price?
With a trailing stop, the trigger price moves in your favor as the market price does. An order is placed only when the price retraces by the preset percentage.
Here's the current price: $BTC Current price: 83053.45 (24h +0.46%).
Funding fees are a cost too, and the longer you hold a position, the more important it is to factor them in.

#BTC

This is just my opinion; trade at your own risk.