Investing with many altcoin kinds maybe less profit because our money put in multi altcoin kinds, but when we use our investment only for one altcoin when price up we can take much profit but have faced big risk because when price down our money lost all because just invest with one altcoin kinds different if invest with many altcoin.
It's kinda true that investing in multiple altcoins might give you a less profit and a slow progress in giving you a profit because even there are altcoins which are slowly increasing it's price, there are also altcoins which are slowly decreasing it's price that it doesn't give you any good profit. So it will be better if we only invest in altcoins that has a potential to increase it's value like bitcoin in the near future.