Short, short stories
Flash fiction stories are short.
A novel is about 120,000 words, and short story is about 10,000 to 20,000 words, flash fiction is typically under 5000 words.
Flash fiction is a story that can be read in under twenty minutes.
Flash fiction stories are an excuse for a writer to have a day dream about something, then write it into a story without the hassle of creating a novel from it.
And the reader gets to start and finish a story during lunch time.