At Crooked Timber, Henry ignited a surprisingly long thread on a subject near and dear to many a reader's heart: authors who have not just worn out their welcomes, but worn them out so badly that readers cringe, snivel, and whimper at the very thought of their books. (So far, Orson Scott Card seems to be the winner--or loser--by a Secretariat-like margin.)
This thread reminds me, though, of a related phenomenon: people who feel obligated to press on, dutifully or otherwise, with a television series or a film franchise--even though they announce to the world at regular (and, to be honest, aggravating) intervals that said series or franchise is relentlessly bad. Unbelievably awful. Mind-blowingly terrible. (Etcetera, etcetera, etcetera, as the King of Siam likes to say.) Thus, people trooped off to see the second and third Star Wars prequels because, goshdurnit, they had invested themselves in this story; just because the execution left something to be desired (a lot to be desired...) didn't mean that they were going to act like the proverbial rats. Similarly, when television shows go off the rails, die-hard fans may rant and rave, but they'll grimly announce that they're sticking it out until the bitter end .
This glum devotion seems to be a by-product of the serial format. If the viewer abandons ship (or, at least, abandons narrative) in the middle of the plot, then there's no future payoff for the initial investment of both time and emotion; people want to know what happens to their favorite characters, want to see the villain get his comeuppance, want to find out what is hidden behind magic door #3, and so forth. In some respects, the Internet has made it easier to drop the series itself--either temporarily or permanently--since the unhappy viewer can simply follow the plot by reading the fan boards. Payoff without pain, I suppose. At TWoP, for example, I've noticed posters who stop watching a show for months, then return to it once a storyline ends or a much-loathed character rides off into the sunset; other posters abandon the show altogether, yet still contribute regularly to the boards. A given electronic community, in other words, can become the "real" entertainment.
To what extent does this sense of self-imposed obligation extend to the written word? Do people feel that they have a ball-and-chain connecting them to a given author--or, perhaps, to a given series? For example, do longtime fans feel that they must pick up the latest Pern or Xanth novel? (Are there still Xanth novels? I don't think I've read Piers Anthony since high school.)
 The flip side of this coin, of course, is the fan who triumphantly announces that s/he will stop watching after such-and-such a date.