It is hugely effective to have multiple physical books around you on the same subject at different levels of detail and different explanation approaches.

It makes it very easy to switch books in midstream if you get stuck, gain more understanding from another book, and then come back to the original book with renewed insight.

Getting stuck... that's a killer. Now, if I've decided to learn something, I get at least 2 books on the same topic. If one author's explanation doesn't click for me, it's good to have that second book for a different explanation.

It can put books in perspective. Many books literally only have one chapter worth reading, many authors don’t have great pacing or have many chapters or blocks of pages that are not good.

If you grab a few books and go through the table of contents, and flip around or drop a book for a bit for another book, you’ll get a good sense of if the book you’re trying to consume is even good.

Basically destroys the notion of ‘curling up with a book’ and takes them off a pedestal.