Actually it is one of the hardest part of being a trader, it is not easy to exit in trading because it requires a lot of analyzing in order to know the best time to exit. I always using indicators for me to know the best time to exit and enter in the cryptocurrency market.
Yeah a trader must have an indicator when they have to sell, buy, or cutlose. of course the indicator must be made, so that when something happens in the market, they will not be confused about what they have to do, Usually some people will exit when prices fall to 5%-10%