You need to reasearch about the coin you wanna invest.. some coins are pure... shit and some other have the potencial to be something special.. but this is no reason to be fool when you are investing your money you still can lose because the people maybe don't see the same potencial.
Indeed you need to think about the future it has if it has one of course and if the market can be profitable.
So long this is the fact it is worth investing in altcoins if you are asking me.
With a lot of altcoins in the market you cannot just blindly pick what to invest, you need to study them all and also consider the volume, the greater the volume the better as that would prove that people are trusting on their money with such project.