I love this type of questions because I’ve always been a fan of the books rather than watching the movies. I’ll try to be objective on this answer. Reading a book involves more important factors when you compare it to watching a movie. For example, the portability, the duration of the entertainment and the link between the book and the reader.
You can carry a book anywhere and you can read it whenever you are free. Depending on the reading speed of each person, this entertainment can last way more than 2 hours. If you decide just to read some chapters per day, maybe it will take you like 2 or 3 weeks to finish the entire book or maybe you are an addict (like me) and have to finish it as soon as possible. Whatever the case is, you control the time of the entertainment. Isn’t that cool?
The ability of imagining the world with the characters in it is like giving life to the entire story in your own way. When you are reading, you put a little of yourself to complete the things that the book is describing to you and what isn’t in the pages. Also, on the books you can relate more with the character. Depending on the point of view of the narrator, the author will want you to feel how the character feels at that moment.
It’s funny that we always have this hope that the movie is gonna be just like the book, but truly it’s hard to put all the experiences and preferences of millions of people in just 2 hours, in one movie. The imagination of every person can be unlimited and the link that all of us experienced when we read every single page, every phrase or thoughts from the characters is unique, and for me the personal link that every reader can create with the book will always prevail against what the movie adaptation offers.