Even if the big coins have had big dips in recent days, they have also had bounces, meaning that there are still strong buyers who bought the price up to fair levels. Have a look at for example the BTC and ETH charts to see this. Furthermore, even if these big coins are down this month or whatever, there are many altcoins that continue to perform well with respect to other altcoins. Perhaps you could look into the altcoin markets to see what I'm talking about. In other words, sometimes when one coin falls, this causes other coins that are traded with it to go up..