I disagree. A movie is defined as best on certain objective criteria used by the critics. As long as it fulfills them along with the entertainment value it could be defined as best.
Now there are some films often classified as masterpieces which are so gruesome in their portrayal of human cruelty and barbarity that not everyone has stomach to watch them again with the same fervor.
For instance, take example of movies like Schindler's list and The Pianist. Both well known classics known for their accurate picturization of brutalities and atrocities committed by the third reich on German and Polish Jews.
Some of the scenes are so moving and filled with absolute disgust that it's not in everyone to rewatch them as they would a light hearted comedy.
That's my opinion and of course you are allowed to disagree.