"Yeah this book had so many adaptations so what's the point in another one? It's not like it's Shakespeare where you can change era, country or actors and see something different. This is almost always the same no matter how you put it.
Here's an idea for filmmakers: make a movie based on a book that has not yet been filmed! There are a lot of books like that, not to mention events in history that also have never been put on screen. Or even plays like for instance Arthur Miller's "Finishing the Picture" which I would like to see/read but it's not available in either format. Or for instance I heard there was an interesting play called "The Jerusalem Syndrome" by Joshua Sobol - why isn't there movie about that or published work?"