Everyone who conducts crypto trading must already have principles and know about profit or loss. My principle is that I will never sell when I see the results will lose, I better hold when the coins that I have bought are decreasing in price (holding is not afraid of losses) but part of the strategy. And I will sell when I increase, although I will definitely sell a little. Never be afraid to experience a loss, because loss is one of the risks in trading. But you must have a strategy.
In trading, sometimes you must sell your coin to stop your loss before it get worse.
Many coins are falling to the price where it far from the price you buy, need long time to recover.
So, you can hold if the coin price falling, but you need to hold for long time which can make you become investor rather than trader.