Another element of fiction that is always compelling is contrast (the other is change). There is something inherently striking about two opposites placed in close proximity, whether that is the differing personalities of lovers, a scene of wild waves battering an immutable cliff, or the starkness created by positioning black against white. Contrast creates an imbalance that evokes a sense of drama and so for storytelling, contrast is a great writing technique.
Contrast can come from opposing character personalities (George Milton and Lennie Small in Steinbeck’s Of Mice and Men), contrasting settings (the Shire vs. Mordor in Tolkien’s Lord of the Rings), initial victory followed by defeat (Santiago vs. the sharks in Hemingway’s The Old Man and the Sea), or conflicting desires (Ennis Del Mar and Jack Twist in Proulx’s Brokeback Mountain).
Action can also become more interesting if exploiting contrast as a storytelling device. For instance, having a character evade their hectic family by briefly shutting themselves in a quiet bathroom; the starkness between clamour then calmness will feel almost palpable to a reader, enriching their reading experience.
Here are a variety of professionals detailing ways in which contrast can be used as a tool in fiction:
In characterisation:
(…) contrast between the two main characters promises entertaining sparks, and it’s therefore appealing. (Writing for Emotional Impact, Karl Iglesias)
In subplots:
(…) subplot is used to contrast how the hero and a second character deal with the same problem. (The Anatomy of Story, John Truby)
In plot structure:
The closing image, or denouement for all you classy lit majors, is a bookend of sorts that shows a good contrast of where your lovers were at in the beginning compared to where they end up. (Romancing the Beat, Gwen Hayes)
In dialogue:
“Going over to the school tonight? Like me to take that for you?” This is informal and can be used to suggest familiarity, terseness, or limited schooling. It can also be used for contrast if the other character speaks more formally: “Are you going to the school tonight? Would you like me to take that for you?” (The Art of Character, David Corbett)
In suspense and tension:
The crime writer and war reporter merely increase the extremity of this contrast between important and unimportant detail, converting it into a tension between the awful and the regular: a soldier dies while nearby a little boy goes to school. (How Fiction Works, James Wood)