Why are fantasy books so unsatisfying?

I keep having the same experience. Someone recommends a fantasy series, or a fantasy series wins tons of awards, and I'm hungry for a good fantasy, and so I finally take the plunge.

Most of the time, I'm disappointed.

It comes down to the world building, I think. 

Most fantasies I read seem half-baked and/or incoherent. I can tell when the author finally figures out the world they're writing about, usually well into the book. But even then, most fantasy authors aren't consistent. The premise is often gimmicky or obviously intellectually constructed, and yet they are rarely original.

When they are original, they are so artificially constructed that they are annoying. That is, they are trying so hard not to be standard fantasy that they go off the rails.

These misses are mostly latter-day fantasies. When I first became disillusioned with fantasy books was because they followed the formula a little too much. I went away from reading fantasies for a couple of decades, though I was lured back on a regular basis by someone's insistence that THIS fantasy was different.

And they rarely were.

Well, which is it, Duncan? Too standard or too different? Will anything satisfy you?

I don't actually care if it's standard fantasy or a upside down version of one--as long as they are well written, consistent, and well thought out.

Every decade or so I find a series I like. Which is pretty slim pickings. I'm probably a little too picky. Maybe I was spoiled by my early discoveries. Lord of the Rings; REH's Conan; Narnia; the Earthsea Trilogy; the Elric books-- are still the best fantasies out there. I found that old pros in SF also constructed some very satisfying fantasy: Jack Vance, Robert Silverberg's Lord Valentine's Castle, that kind of thing.

But pure fantasy writers struggle to really nail it.

One problem is that almost all fantasies are not stand-alone. So you have to read an entire series-- which, if I don't like the first book, I don't--and that is very unsatisfying.  SF and mystery books are more often stand-alone books, even if they are part of a series. So that's what I've been reading for the last 30 years.

I always thought when I came back to writing that it would be fantasy. Instead, I've been writing soft SF, thrillers, horror, and dark fantasy. Epic fantasy is something I want to try sometime--but only if I can avoid the above criticisms.

Of the more recent fantasy series, I can narrow down the ones that I thought were great to a few:

"A Song of Ice and Fire," by George R.R. Martin is every bit as good as it is given credit for.

"The Kingkiller Chronicles," by Patrick Rothfuss, while not perfect, are very good.

and a third, less known series, that I highly recommend;

"World of Five Gods," by Lois McMaster Bujold.

That's about it.

I'm not going to say the name of the writers and books that I haven't liked. But believe me, I've tried most of the ones people are likely to recommend. Many fantasy books are competent and moderatelly entertaining, but I'm looking for something more than that.

What happens whenever I talk about this is that people will say, "Oh, you need to try this!" and then the cycle starts all over again. I'll be sucked in again, because I truly love fantasy. And maybe I'll get lucky.

In the meantime, back to my SF and mysteries.