Question

The main goal of a fable is to

Answer 1

the purpose of a fable is to teach a lesson about a human weakness or folly

Answer 2

The main goal of a fable is to:

teach a moral

Most of the fables I have read are either implicitly or explicitly teaching a moral lesson. The usual flow of events is stating the main problem of the characters involved and then providing a solution to it which later on realized by them.