Book vs. Movies: Is the book always better?

People who read frequently rarely like the movie version of their favourite books. There have been some great movies made from books, but typically they tend to disappoint the readers by not being "just like the book". A film made from an adapted screenplay simply does not have the same results as reading the book.
Books and films are different entities. While films leave little to the viewer's imagination, when you read, you are creating you own movie in a sense. The creative process undergone while reading a book is distinctly different from viewing a film.
The casting directors don't always give you what you want. As many would agree that casting Tom Hanks to play the role of Robert Langdon in Da Vinci Code and Angels and Demons was a significant mistake. Highly elaborate sets may be wonderful but they may not be a faithful portrayal of your interpretation. You may find yourself disappointed by movie versions that don’t live up to your imagination.
Some might theorize that perhaps we like that which we knew first (which in most cases is the book)- You read the book, you love it, you find out it has been made into a movie, you watch the movie and end up disappointed. The problem, however, with this theory is that it should work in reverse as well i.e. if you watch the movie first, you should prefer it over the book. This does not happen nearly as often. Sure, the movie first leaves a lasting impression of how the characters look but it is usually fine to imagaine them that way when you go ahead and read the book. The details in the book end up enriching the story you already know and you still come away saying the book was better.
A perfect casepoint is the recent release Angels and Demons, an adaption of a popular work of fiction by Dan Brown. I loved the book, couldn't put it down. The movie on the other hand was a complete disaster.
Had i only watched the movie without reading the book beforehand I might have come to the conclusion that I do not wish to read such a mediocre book.
Of course there are exceptions to the every rule. There have been occasions where a filmmaker has taken a great book and managed to make an even greater movie. A few films that I considered were better than the book are:
1. The Searchers
2. Ben-Hur
3. Psycho
4. Jaws
5. Gone With the Wind
6. The Shawshank Redemption
7. The Godfather
8. Blade Runner
9. Stand By Me
10. The Princess Bride

Book vs. Movies: Is the book always better?