I think it depend on the project itself, if the project you are hodling is not showing any potentials, it is very wise to sell while you can because not all alts deserve to be hold for a long period of time, you have to see potentials or activeness on the part of the team to hodl.
no one can predict with certainty the development of crypto and altcoin currencies and in my opinion the development of crypto currencies with any coin depends on the investors themselves as investors we must be able to take advantage of every opportunity that we will get our confidence and patience