"If you find that you consistently don't read the whole book, you aren't picking up the right books."
-Read to Lead
I really liked this quote in "Read to Lead" by Jeff Brown & Jesse Wisnewski.
I've found myself over the years picking up a book and enjoying the first couple chapters, then putting it aside. Formerly I'd feel guilty, and force myself to read through the rest of it as in my mind I would see it as not technically "reading the whole book" and that there might be great points in the later chapters.
I really liked the perspective that you don't need to finish every single book, and that if you find yourself constantly having to force it down your own throat, you may not be picking up the right books.
With some of the more recent books, especially those produced by today's thought leaders I find it difficult to read through the whole thing, and many times their ideas could have been expressed as well in a single chapter vs dedicating a whole book to it, and I find that most get repetitive after a couple chapters.
It's gotten to the point now where if I see a book is around 50-60k words and published in the past couple of years, I'm highly skeptical that the later chapters are even worth reading. As a lot of the time, they are "optimized" to promote said thought-leader and their business, which isn't bad by any means, I've just found it typically reduces the amount of actual value produced in the book.
The books I've found infinitely valuable and I frequently re-read are those written in a purely informative way without any expectation of return from doing so. Some of my favorites in these categories are autobiographies, and some books I like to call "old wisdom."