Before entering any cryptocurrency market you should have first set a target profit on when will you get out both short term and long term investment. if you decide to go for short term of course you will want to get out when a coin you bought has reached its peak and we dont know when or what price range is the peak that is why you have to set a target percentage profit 5 to 10% is enough. when going long term you want to make huge profit but you will never know when to sell until it drastically increases its value.