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.
I think,cryptocurrency is zero sum game. When we got profits and sell it at high, some one buying our coin at high price. Only people who able patient and know when the right time to sell will gain proftis. I am agree we should not afraid with loss because it give us knowledge to make profits