Most people know the premise and few notice how carefully the structure does its work.

The frame does the heavy lifting

A king, betrayed, marries a new bride each night and has her killed at dawn. Shahrazad marries him and begins a story she does not finish. He postpones the execution to hear the ending. She finishes it the next night — and begins another.

Because of that frame, every story inside carries a stake that has nothing to do with its own plot. A merchant’s misadventure is suspenseful not because we fear for the merchant but because the storyteller’s life depends on it holding attention. That is an extraordinary piece of construction: the frame lends tension to material that could not generate it alone.

Stories inside stories

Characters within her stories tell stories, sometimes three levels deep, and often to save their own lives too — a merchant buys time from a demon by telling a tale. The whole book is an argument that narrative is what stands between a person and the worst thing that could happen.

Read that way, the ending is the real point. She does not win by cleverness alone; a thousand nights of stories change the person listening.