There needs to be something you can DO with it, and there has to be a way to attract adherents to the coin.  They key is therefore the ecosystem that is set up around it.  Is it on exchanges?  Does it have a marketplace?  How about a casino for those that like to gamble?  And of course a faucet or pay to watch site to draw in new casual users. 

Too many folks just fork an existing coin and hope it works, put some time into developing a back end infrastructure of things to use it for rather than just "forking it and hope they come."