It depends on your strategy for me I don't wait until 20% for me to take profit, most times, some coins hardly make such gain, but taking profits like 5% or 10% many times could be a good idea, coins normally makes such gain many times before it could go as high as 20%, so I believe in taking profits as soon as you see them and re buy when it dips down again.
That's a great idea, it's better to take small profits rather than give up the opportunity to sell right? most people make the same mistake repeatedly because they are too greedy by waiting for the price to rise higher precisely what happens is the price decreases due to certain factors, so use the opportunity that comes as good as possible don't be too greedy
Actually, it is the other way around
Most people are in fact too impatient, close too early, and book profits without letting them grow ("let the profits grow", yeah). It could be loosely claimed that impatience beats greed here, though being impatient is not the opposite of being greedy. If you are greedy, it is more likely that you are going to make an early exit specifically because you are overly greedy and can't wait, i.e. for being too impatient. The number of people who wait for too long is actually quite small, and it is so due to lack of an overwhelming greed