Let's give an example of you bought 100 BTC at 9000$ Price and the price went 9010$ in seconds then you sold, so your profit will be 1000$, may 500$ fees, but the another 500$ you made it profit in seconds!
Let's discuss at the point!
Now take another example OP, suppose you brought bitcoin at $20k and in a day the price went to $16k, now please calculate the losses and see whether bitcoins is get rich quick scheme or more of a hold for a lifetime scheme. I guess you can clearly see by this post that only an experienced person can see past minor market fluctuations and also should be patient enough to wait to see profits and not sell at the time of panic selling in the market.