what is good photo?

I think, there are two kind of photo. good photo and not good photo.
But I didn't know, why I feel good. Just good photo is good, I thought.

Today I'd noticed that good photo has story. its interesting and important idea for me.
In normally case, two or more objects in a picture. and when I see a photo, I can feel connection between objects. and that connection changes story in my brain.

Example, a photo has two objects, a dog and a rock. The case of the rock was taken accidentally, that objects has no connection. the dog is a dog, and the rock is just a rock.

But how do I think about case of the dog is gazing that rock?
I can get notice that the connection between that objects. and that connection lead to a story about their.

I decide to say "That photo has dipth." when photo has story.
I want to take many photo have each of dipth through self practices.