For me, it’s Jude the Obscure. That book is easily the worst book I have ever read, without a single redeeming quality, other than that it finally ends. I only finished it because Far from the Madding Crowd was so damn good.
But really, Jude is the gold standard of awful books, in my opinion.
What’s your so-awful-it-deserves-shelf-space book, if you have one?
Or am I just weird?
There are some books which are very much a product of their time. The Alchemist is one, as is Zen and the Art of Motorcycle Maintenance, and the scribblings of people like Richard Brautigan. If you read them in your late teens/early twenties when they first came out, they were so much part of the zeitgeist that you were swept along and thought they were wonderful. Where you reread them decades later, you realise how badly written and shallow they are, but they still have memories of a special time in your life attached.