I have the tendency to fall in love with a franchise, give it all I have to offer in means of art and writing and whatever, view everyone else's art and writing, listen to the music for hours, create my own characters, ponder the plot, and once I've milked it for every last thought I lose interest and it takes a back seat.
Don't get me wrong, I will never 'not care' about these universes-- Ecco the Dolphin, Oddworld, Pokemon, Bully, Phoenix Wright... I just get way too over-excited...