A story is a struggle.
I’d love to leave that sentence as a complete answer, but I’ll add a little more here.
Conflict doesn’t mean fight or war unless you’re thinking figuratively. It’s something a character pushes against. Maybe it wants to be something (like the girl/boy of your dreams returning your love), or maybe it wants to stop being something (like a bad guy attacking town), or maybe it is going on some journey.
They are all struggles. Human beings want, and the world is fighting that desire in some way.
The best stories usually have three characteristics.
1. Small disputes are being resolved on the way so that the significant conflict can be resolved. (This structure is very evident in children’s movies like Toy Story or Cars)
2. Interesting characters. People usually need someone who acts (or wants to act) that way, but the other characters also need to be familiar somehow. (Fight Club does both—Ed Norton’s character is “us” in the film, Brad Pitt is the person we want to be.)
PS- I know we shouldn’t be talking about Fight Club. Excuse me for that.
3. If someone listening/reading/watching the story can live vicariously through an interesting character, they will become engaged and curious through that character’s internal conflict. Maybe they have to make a moral choice; maybe they have to make a courageous choice; maybe they make the wrong choice. (Both of the previous examples fit here as well. For example, Woody from Toy Story is torn between loyalty and jealousy, with Ed Norton second-guessing the movement he created.)
I would add that the “wrong option” is a great way to cause minor conflicts in the first element I listed. If a character behaves the same way you behave and things turn pear-shaped, you’ve got something. For example, in horror movies, people usually talk dumb, and we lose our relationship with the character. But when they do precisely what we think is a “smart” thing and create more significant problems, we buy into them emotionally.
A familiar character struggling to address a problem is the main thing to happen in any story we enjoy.
The story is a life imagined by words. Its existence is as old as life itself. Life is a set of struggles hence the story.
Delicious food is seldom good for health; what is healthy rarely tastes good. Clothes that are comfortable to wear rarely look fashionable, those that look fashionable are rarely comfortable to wear. If it’s both, there’s rarely a reasonable cost. Practices full of joy and fun are rarely allowed in society; those allowed are no fun to yearn for.
The more conflict there is in the story, the closer it is to live and the closer it is to reality. A conflict-free story is not a story, and that’s why the ‘Happily-Ever After’ comes to an end.
For example, Ramayana is more significant than a life story. It is full of life, there are so many struggles at every turn, but it ends when ‘Ram-Rajya’ is established, now there is no struggle, no one is interested, even the saint writer, Not even those whose primary purpose of writing was to sing the glory of their deity.
The story escalates the tension as far as possible and reaches a climax of lasting comfort, consolation, or irony.