I find "experimental" novels truly awful. The ones where the author is attempting to subvert narrative conventions.
Well, some experimental novels are awful but some are brilliant... It seems a slightly fatuous distinction.
(I also find so-called classics like the piffle written by Jane Austen and the Bronte sisters plain annoying, but can appreciate they are not terrible books in the true sense of the word).
Why mention Austen and the Brontes in particular? And why cite only women writers when mentioning "so-called classics"? Do you feel the same about Dickens, Trollope and Thackeray? Or is it that you feel women are particularly prone to writing "piffle"?
Austen and the Brontes have very little in common, apart from being women. In both style and subject matter, Austen is nothing like the Brontes. And Austen is a brilliant writer - incredibly elegant prose, and very witty. I'm not much of a fan of the Brontes. Wouldn't call them "truly terrible", just not my thing.
DH Lawrence and Thomas Hardy are two "so-called classic" writers I've struggled to hold an interest in. They tend towards the turgid.
Dan Brown goes without saying, but since everyone else has mentioned him, I'll add my vote. Shockingly bad.
d.