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 ... 
lol wtf man but you must be right because people claimes that eth , ripple ,bch are shitcoins . there are also some that called btc a shitcoin .
but for me i can say that these coins are far from a true shitcoin because they are somewhat useful and have thier own unique abilities or usage . most alts are not a shitcoin but most tokens yes . its easy to spot a real shitcoin by basing only on its appearance or name because most shitcoins came up with odd names and odd coin icon/design .