If that is about altcoin, we could be wrong in saying that one or two coins can be the hidden gems because, from all of the altcoin lists, it is very difficult to know which altcoin can get a massive increase in the next altcoin season. Every altcoin, especially in the 10-50 coins lists, has the potential to increase, so if you have big funds to invest in the altcoins, you can buy one by one of the coins, so you can expect to make some profit from that. But that will not be a good decision because you will confuse to manage your time checking the coins one by one.