It is better to have many altcoins in order to have more money to trade and earned a lot. Having a lot of altcoins in your hands will have a greater chance to earn big amount.
choosing only 1 altcoin has a big advantage and risk, I will buy lots of special proportions of altcoins, and I will buy it with several conditions, must have transaction volume above 500 BTC per day and listing pass several major exchangers such as binance, bittrex, bitfinex
of course at first it was really hard to identify what are the some of the altcoin that are have to choose with and you really need to pay an attention with this too. And when youare know some strategy with it for choosing another you have an idea with it too.