Comfort.What would be the point?
Indeed. Adaptation is a process and needs to weed out elements that don't fit within the medium; case in point, Sam bring tempted by The Ring. Great literary prose but poor cinema.Douglas Adams very specifically made a point of making sure that the radio show, novels, television show and movie for Hitchhiker's Guide to the Galaxy were different from each other.
Starship Troopers and Baby Blues are two I was more disappointed in but there's still value there and it doesn't have to be just for fans.