> Similarly I've encountered a lot of fantasy that was all about world-building but where the book itself just went nowhere. World building is kind of easy compared to actually writing a novel with a compelling story. It seems to be common for aspiring fantasy authors to spend years doing the former and never getting round to the latter.

I'd actually be interested to read some of those - I wish there was some kind of standard media form for that. E.g. I enjoyed reading the Eclipse Phase sourcebooks much more than actually playing the game. And while I didn't actually enjoy Christopher Priest's The Islanders, I liked the idea of the form.