The only thing you need to do is to make a good research about a particular coin. If you have investigated and researched thoroughly then maybe you won't end up with the loss. Most of the altcoins, when they are released on the market after ICO don't last long but their whitepaper explains everything and if you invested smartly you will know when to trade with them. Keeping all that altcoins is risky cause few of them will rise up and perfect solution for that is constant trading. There will always be altcoins cause it I the new trend of developing projects and for some scams which you must watch of. You should invest 1 to 2 months if you have a profit then sell, if you do not profit then you should sell because there are many altcoin for you to choose and not necessarily altcoin it. You can also invest in ICO projects because the opportunity x2 assets is very fast