As far as i know about it, Investing in altcoins may be more risky. But it can bring you a lot of more profit then just like bitcoin. When you look at some altcoin who you can buy at the initial coin offering for 1 cent, they have potential to go 100x to one dollar if the max supply is not to high. So the reason why so many people invest in altcoins its because they want to make more profit.