I can remember the first King book I read. The Shining. I can also remember the first one I hated. The Dark Half.
I think (but I'm not sure) that The Dark Half was the first one he wrote after he quit smoking, drinking, and drugs. I didn't know this at the time, I just thought it sucked. I suppose if he did it under those circumstances it isn't half bad. He gradually got back into his groove in the 90's, I thought, and the culmination in my opinion was Wizard and Glass.
But then he got hit by the van. The first post-accident book would be, I suppose, From a Buick 8 though some of this had been completed pre-accident. It's not bad, but a little uneven. Then we get into the Dark Tower finals and it just goes completely off the rails. I think the reasons for this are probably fairly complex even if the basic suckage is evident. I think the self-indulgence is a big part of it. Not even so much the metafiction itself, it's just got this weird vibe going. It doesn't work.
Sometimes I think his meditation on writing works better. I absolutely loved Lysey's Story. Heck, I think it's his best work. Even better than The Shining and The Stand (formerly my favourites).
But you know... I don't think I could tell you why. I don't know why I liked it so much. If pressed, I'd guess it just happened to be something I read in the right time and place and it clicked. I love it, but simultaneously I know I cannot objectively say it's a good book. I don't think it's that kind of book. It's one that different people will take differently. I lent it to a friend and she returned it with ill-disguised disgust. Guess she didn't love it like I did.
Some of what's going on in the Dark Tower later books might be like this for readers, if we're a bit generous (by this I mean that the visible majority I encounter seem to fall on the side of 'it sucks'). Some of it might be bits of fanboy, too. What I do know is that for me reading them was an awful experience, and I can articulate some of why that was so but a lot of it I can't. It could be said with some fairness that I just didn't "get it".
I find it difficult to be purely objective about Stephen King's work in a way that I don't experience with other writers. I can, for example, point out where Tom Clancy took a precipitous nose-dive into complete garbage and never came back (The Bear and The Dragon remains for me the single most disappointing book ever, and the only one that upon completion I unceremoniously dumped in the trash, $40 hardcover or not).
Where King is different is that the man is just so passionate about writing. The process, the love of the craft. As Dudalb points out, this sometimes acts to taint the well he draws from, but it also introduces a weird layer of complexity. Should I read the Dark Tower series as story, or as exploration? Is it better if the latter? Equally important, is that a fair expectation to make of a reader or does it signify a failure in the writing? That's a question I can't answer, and this thread shows that we fall on all sides of that issue.
As objective as I can be on it, I think it was a mistake. Perhaps it served him therapeutically to go where he did with it. Perhaps it was just coasting with the wheels off. Maybe this is even, in basic substance if not in specifics, where it was always intended to go and our expectations would have set us up for disappointment anyways.
For the most part, I'm with Dudalb. I can see the other side of things too, but I think it stretches the forgiveness factor quite a bit. I'm willing to take another crack at them with an open mind and try to see them as something more, but I have a strong suspicion I'll still come away thinking of them as an exercise in literary autoeroticism.