That question is endlessly fascinating to me. Story is a waking dream in which we reframe our lives in symbol and metaphor to find meaning. Story is an entertainment, for the one spinning the story and for the audience.
Story is a learning tool and a teaching tool.
All that and more. Exactly what story is and how a story ought to be structured is a topic constantly evolving and always in debate. They range from serious to completely giddy. You may like some of them and dislike others. Which is good, because if everybody liked the same thing all of you would eat up all the chocolate in the world and not leave any for me.