What are the major elements of a fairy tale?

A fairy tale has three main parts of the story. In the beginning the protagonist has a decent life but isn't content with it such as in the little mermaid where she isn't content with her 300 years of life and wants an immortal soul, or the girl who tread on the loaf who is very pretty but she is vain and isn't content with her good looks. In the middle the protagonist attempts to achieve their ultimate goal, but fails and their situation becomes worse such as in the little mermaid how she goes to the see witch but instead of gaining an immortal soul she is stuck without a voice and having every step hurt like she is stepping on knifes or in the girl who tread on the loaf she walks on the loaf and sinks into the devils kingdom where she is held as a statue. In the end of the fairy tale the protagonists situation improves often in an unexpected way such as in the little mermaid where she becomes an air spirit which gives her another chance at an immortal soul or in the girl who tread on the loaf where she has an epiphany and realizes how vain she is.