By which I mean, books that are generally good, but have a lot of really pointless padding.

Classic example: lord of the rings.
Remove all the elf bollocks, poetry and songs, send Tom bloody bombadil to the mines of Moria.
And then you'd  have a book nearly as perfect as the hobbit.

It's weird.
Peter Jackson actually removed the crap for the lotw films

Then faced with a perfect book with zero padding, he then went and completely ruined the hobbit by adding an awful lot of totally nonsensical bollocks.
It would have 2 good films. It's a short book, in no universe was it ever going to make a watchable trilogy.
And it didn't.

So that's where I'm coming from.and the book that promoted this thread is Ilium by Dan Simmons.

The basic plot is very good and pretty interesting.
But the damn book is littered with very long passages of academic discussion on Shakespeare's sonnets, Proust's poetry and  a lot of homers Odyssey. None of which has any real bearing on the general plot.

I'm only a couple hundred pages in and already I've probably skipped 20 or 30 pages without missing a single word of actual novel.

There are pages pretty much just listing who died at the siege of Troy and in what order.
It's almost relevant to the plot. But not in the minutiae that Mr Simmons insists on using.

Why do writers feel this need to pad out perfectly good books with pages and pages of nonsensical rubbish ?

So what books would you like to edit down to something more readable ?