Back in the times where books were all bound in similar styles and materials I agree that you couldn't judge a book by it's cover. A tatty book may be that way through neglect or through extensive use by eager readers!
Now things are different. Very often you can judge a book by it's cover. The publishers will have looked for illustrators/designers working in a style sympathetic to the book's content or desired target audience. Your eye will naturally be drawn to the symbolism of things you like. This symbolism then becomes a language between your brain and the book publishers.
As social preferences evolve, so does the language. You'll notice if your library has many old* books that you may find it harder to judge whether you'll like the book because the visual language used is not one you're familiar with.
*old as in copies printed before you were able to read
If you fancy challenging yourself to read something different then pick up a book with a cover you'd normally skip straight past. You might find a hidden gem or unlock a whole new genre you didn't know you cared about.
Below is my collection of book covers I consider to be beautiful which I will add to over time, as and when they catch my eye. If we have similar tastes then I think you'll enjoy them!
illustrator Sarah Gibb
designer Kirk Benshoff
designer James Alexander at Jade Design
designer Peter Saville
