This amount of gain does not happen that often and it only does on very low cap altcoins which is very difficult to know what could increase that much in the future. If I would experience that kind of gain I would probably sell all that coin at 1000% gain. That coin with that kind of gain will surely have a pullback and you don't know how deep it will be, if that happens you will just regret it because you did not take the opportunity to sell it when it was at peak price.