One that stuck out for me as particularly bad was Michael Moorcock's Eternal Champion series. I read and enjoyed the Elric books back in the 80's. They weren't particularly well written, but...ELRIC!! STORMBRINGER!!! (I almost wrote Black Razor there....). I trawled the second hand bookshops in Newcastle and bought pretty much the whole Eternal Champion series....Erikose, Corum, Hawkmoon, Jerry Cornelius.....
I started with the Erikose (I think that was his name) and was pretty unimpressed. The writing was, if anything, worse than Elric without any of the great story and characters, but I pushed on with Corum, like you do. It was, if anything, even worse. Terrible writing and recycled ideas. As far as I could see, Corum's entire personality was "I have a silver hand". I never did find out Hawkmoon's backstory because the whole lot ended up being donated, including the Elric novels which was a shame. I've since tracked down most of the Elric stuff. It's there on my shelf, but I'm not sure I'd ever re-read it.
Let's address another elephant in the room. Conan... I LOVED the Conan books back in the day. They were what I first read, along with Sword of Shannara, in the early 80's when I met the weird kids in high school who got me to roll out my first character (human fighter, made L9, gave me my first twinge of LFQW envy). There was an imprint, by Orbit I think, of about 20+ books and I worked through them all, buying one each month with my pocket money. Loved 'em all. Howard, Offutt, Spague de Camp. Eventually, my wife informed me that we didn't have space so they were donated. A few years ago I bought the Howard Conan stories in hardback and settled down to revisit the pleasures of my youth, which turned out to be a big mistake. It wasn't as bad as Moorcroft, but I couldn't get past the one-dimensional characters, clunky dialogue and poor writing to see the magic that thirteen year-old me had seen. I should have learned my lessons from Blakes 7.....
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