For some highly complex books, a reread is more like a re-analysis of the text based off of ones existing knowledge. There will be nuances and details that were missed the first go around, that is uncovered the second time around, making the understanding of the piece richer. It’s like mathematics- everything is built on fundamentals.

(Some people also derive comfort in familiar stories.)

Well, to your first point, because I value depth over novelty. The second time should be better.

To your second point, to quote Prince, "There is joy in repetition".

More than 90% of things that are new to me disappoint me. I don’t know how to find new things, especially fiction, with the expectation that it will hold my interest. Whereas something new from my favorite author has much better odds, and rereading my favorite novel is a sure thing.

1. It’s totally easy to miss things when reading: certainly little delightful details, or even whole ideas or plot points.

2. It’s not like there are millions of great books out there. Some entertaining ones, some informative ones, a few that are both, and a very few life changers.