Commercial literature seeks to produce specific mental states and emotions in the reader such as suspense, anxiety, fear, mystery, romance, intrigue, and curiosity about new or strange things among others, with the goal of providing the reader with an exciting experience. When writing we should create situations that produce this kind of mental states or emotions.
Entertaining literature favors a well-defined plot, with a clear beginning, middle and ending. This way the reader is not concerned in decoding the order of the story or in trying to understand what it is about and then becomes more open to experiencing the emotions being narrated. However, if pieces of the beginning are skipped, the order of pieces of the story is altered or certain aspects of the plot are hidden, something has to be done in order to produce mystery which is one of the mental states we are aiming for.
In general, entertaining literature has a better defined morality. There are “good” and “bad”, there is a hero and a villain. This allows more emotions to be experienced because when we relate with a side (hopefully the “good” side!) our emotions lean that way without asking ourselves constantly if it is something that is morally right or not. Literature in general has more gray areas because it tries to explore or portray the moral duality in human beings.