The purpose of flash fiction is to deliver the basic elements of a story—main character, conflict and resolution—all with an economy of words and a punch at the end. This final punctuation can be a twist, a chord of irony, a humorous note. The story can appear to be one thing only to be illuminated in the finale as quite another.
This blink-of-an-eye exercise forces you to create a snap shot in time and build suspense and the element of surprise with harnessed language. If you can wield tension powerfully in a flash fic piece with 500 words or less, just think what you could do in long fiction.
Try it out, be creative, have fun and aim for a knockout. The bloodshed and thrashing of your work, though brutal, will produce a beautiful piece of art.
~Signing off and sending out cyber hugs.