The biggest mistake anyone can do is still holding unto their altcoins when bitcoin touched 60k weeks ago and still holding strong when the fall began weeks ago, imagine someone still holding HEX token when the coin did 40x already? If you are someone like this friend I don't know what your aim is but sorry to say you are doing it wrong. Check yourself cos it's possible you are struggling with greed.
Lets not say its a greed. But seeing Bitcoin's massive growth over past years, its convincing to hold back the coins irrespective of what coins are they. I am one among you who can not wait to take off my profit even if it is just 10%. However, I have learnt that day trading is better but long term trading is the best when I see it from my trading experience from 2017. But yes, as you say, there should be a limit set for profit.