Understandability, Probability, Identification
First, the story must be understood.
The novice is inclined to forget this necessity in his enthusiasm. He concentrates upon the things he wishes to express, the emotions he wants to arouse, the messages he has to deliver, and he is liable to forget that none of his desires will be fulfilled unless the story is understood. The spectator cannot believe in a story, he cannot experience fear or hope, terror, or joy, he cannot feel sympathy or aversion, and he cannot be moved to relief or anguish unless he understands the story.
A writer intent upon making a personal statement might not care how much of it is understood. But if he proceeds without regard for clarity, he must be aware ...