There are a number of shows that have just not held my interest for long over the years, but the characters often hold my interest long after a show is over or I've stopped watching, because for me, the characters and settings to play with are as important as the long-term quality of the show. (Actually, come to think, almost every show I've watched has lost me, often before their run-time is over, because of the quality of writing. There's only one still currently on that's drawn me back in, and one that's kept me interested despite missing episodes because of life.)

In the long run, I take the good stuff, and the fanfiction, and I play with what I want, and ignore the rest. Sometimes including large chunks of canon after they've lost me to boredom (or in the case of a recent one, desiring to hit the producer and writers with bricks, because dude, I like my bad guys intelligent, but not overwhelmingly clever and evil to the point the good guys can never win).