Stweet,
People read fiction books all the time without a purpose. They simply want to enjoy the emotions they get while reading a non-fiction story. It is like going to a movie. People don't go to movies with a purpose they simply want to enjoy the experience. One exception where an individual might have a purpose going to a movie would be a movie critic who is evaluating a movie or film but for the majority of people they simply want to enjoy a story.
But for someone wanting to learn science or mathematics or engineering or biology purpose is absolutely essential and required and the problems you are experiencing have everything to do with you not being clear on your purpose, on you not being clear what you want from the book.
Photoread4me
