They have their strengths and weaknesses, and if these are respected and worked in harmony with, rather than against, then I think they definitely both can work. And from that perspective it is a case by case basis. Unfortunately some adaptations ave been done on the cheap, or have tended to hold the book itself in too much contempt and via far too much from the script.
Books I prefer, but they take a significant investment in time. So movies can be great to experience the story rapidly. And this works for me also.