I enjoyed House for like 6 of its seasons. For me, the unforgivable misstep that sank it came in its penultimate season. Through the whole season, it seemed like they'd been organically building an arc of House's relationship with Cuddy making him a more rounded, healthy, well-adjusted human being, which would ultimately lead to him finding a kind of happiness at last and, presumably, the end of the show. But then it seemed like the writers panicked at such an arc being completed, so suddenly got cold feet and abandoned the storyline, reverting House back to factory default lonely-and-bitter. Only now it felt hollow and perfunctory.
I have up watching House a couple of episodes into the final season. I would surely have done the same for Dexter this season, if not for one key difference. It wasn't announced that House was finishing until after I quit. If I'd known going in that the show was going to be ending, I'd probably have felt compelled to stick with it to the end since I was so close to having seen it the whole way through. That's what has kept me watching Dexter, it's now the only thing keeping me watching Dexter.