What are some books you've bought ages ago, but never have gotten around to?

I buy a bunch of books each year, but it seems less than half of them get read.

Sometimes I'm just satisfied by the notion that I will eventually read the book and never get around to it.
However, I do actually go back to some of these books. For instance I bought Gene Wolfe's Shadow of the Torturer/Sword of the Lictor back in 2015 but recently finished it back in summer of 2018.

Some have sat on the shelf for much longer.

Orson Scott Card's Xenocide comes to mind. I read Ender's Game back in 2013, read the sequel some time in 2014, and told myself I'd get around to the third book (Xenocide) but I never have.

Another one I picked up last year that I've been meaning to read is The Confessions of Saint Augustine.

So, what are some books you've been neglecting? Write them down here to put them to rest, or even better, to motivate yourself to actually read them!!