Kate Chopin is able to write complex short stories in brief lengths for several reasons. In both of the examples listed, Chopin uses a third person limited point of view and spare figurative language.
The third person limited point of view allows Chopin to focus on just one or two characters’ inner thoughts and emotions, which prevents the story from being consumed by too many characters.
In addition, Chopin uses dialogue and interior monologue as primary plot devices. She does not use elaborate metaphors, symbols, or flowery imagery to convey her points. Instead, Chopin is most interested in character development and irony. In each story, the protagonist is a victim of irony at the hands of her husband.
Mrs. Mallard has a heart attack because she discovers her husband is alive; and she is not happy about this. Desiree essentially commits suicide and infanticide because Armand allows her to believe she is black; the reader learns in the last paragraph that it is Armand, in fact, who is black. Each of these ironic revelations is not discussed until the final paragraph of the story. Ultimately, Chopin is able to mislead and hook the reader into a complex story because of her ability to hone in on the most important parts of a narrative rather than tricks of language.