Well, it's very easy, since almost all altcoins are shitcoins, it is sufficient to say that - whatever the currency we are talking about - to say that it is a shitcoin, with 99% probability of guessing ... 
It would be very wrong to say shitcoin by guessing, because not all altcoins are shitcoin, because some altcoins that are already really popular in many exchanges are not included in the shitcoin category.