Depend on how much profits you want really. I mean this question refers to individual portfolio as we speak! Everyone has invested in different coins, some guys might be in profits and some of them may not be in the profits at all! SO obviously the second group of traders will hold their coins for very long time or until the prices get skyrocketed for their portfolio.
So this makes it easier to understand. If you think you have made enough profits then you just skip the coins for now and sell them. Otherwise wait for the right time and you could end up earning huge profits too.