In workshops, my stories would be praised sometimes for including intriguing images or events or tropes in the first half of the story. "That moment with the dog was so cool", I'd hear. "But where did the dog go later on? It disappeared from the story!" Or else, fellow students would note a good hint at some relationship: "I liked the hint of the parents having some mental illness." But they would also note that the problem seemed to disappear. It was almost like I would throw in interesting things in the first half of the story, but I didn't know how to seal the deal, how to bring it home, how to make those things come back to truly complete the story. But without their returning, the story felt incomplete. It trailed off.
I think a lot of us do this; we lay the groundwork for something truly interesting, but we forget to follow through. We get involved in resolving this particular problem in the story, and forget that excellent work we began with the dog or with the mother or with the ice cream. But for a story to feel like it is truly coming full circle, we need it to return to those things; we need to call them back into place. Today, try going to a story you're editing, and bringing up something at the end that you mentioned on the first page. It's a neat little way to make your story feel like it's moving in a real arc.