Besides that coins, he can find many more altcoins to invest, so he can have more ways to make a profit in the investment. But those three coins will be enough for him if he feels difficult to analyze the other coins because we know that many altcoins need to be analyzed to find the right coins. Just remember, don't buy the altcoin when the price starts to increase because you can get a trap at a high price, and that can make you wait for some time to sell your coin.