An interesting thing about fiction/story structure is that it sometimes makes good sense to write scenes that have no causal consequences.
There's a bit from The Lifecycle of Software Objects that I often think of when I think about structure or what belongs in a story. The first part of the story is about a startup that creates digital, animal-shaped sentient creatures called digients. The second main character is Derek, an animator working at the company who animates for example digients' facial expressions. There's this short bit where Derek is at home after work, browsing a web forum. He sees this post about someone's digient not responding to them. That person's avatar (which is also how they appear to their digient) is an animated shower of coins. He suggests that they might have better luck if they used a human avatar. The coins guy says, essentially: Fuck that, I'm not changing for this fake creature. I paid a lot of money for this avatar. Meanwhile, if I recall correctly, Derek muses about this clone kid he saw once at a party who seemed to be a bundle of neuroses.
I think this scene serves three purposes in the story. First, the company (spoiler!) eventually fails, and this scene presents one challenge that probably contributed to that failure. A lot of scenes in this first part are about such challenges. Second, we learn more about Derek. Up to this point in the story I think we've only seen him thinking about the digients as "things to animate" – and he cares about that work, but it's less directly about the digients. Here we see that he cares about the digients as something beyond an animation project, enough to be advocating for them on a web forum after hours. That's important, because he's one of the story's two main characters and the way that he cares matters. Third, we get exposition about how these digients work: They respond to human avatars, not to arbitrary simulated talking objects.
But structurally, it's strange. This scene works, and feels right, and makes sense within the context of the story. It's a good scene. However, this episode has no causal consequences for the rest of the story. It's not like this coins guy comes up again. It's not like the way Derek deals with him (politely giving him some advice) has deep lasting effects in the story. So why do we need this scene? Why not just summarize it and say people wanted to treat their digients like toys rather than like pets or children?
I think it makes sense to include the full scene because of how it sets up for the company's failure. It's to set up for the company's fall. We need a full scene demonstration so that we can "really" understand the reasons that the company fails; if it was just summarized then the failure might feel confusing or arbitrary. But we also need the full scene because it makes Derek's emotional investment in the digients and their 'success' more concrete, thus more real to us. That makes the company's failure land emotionally, but it also sets up for the later parts of the book where Ana and Derek are caring for some of the digients in the wake of the failure.
It seems worth thinking why this kind of scene made sense in this story. I can't think of many scenes like it. I suspect this kind of scene makes more sense in contexts like this one where the characters are contributing to some larger effort where their contribution on its own is not directly causal. In this case the larger effort is the company; you could also think of it as the effort toward making digients successful in some sense. That is: It makes sense because of the scale or kind of story we are telling.
This is weird to think about, but makes a little more sense now that I've thought about it.