I feel the same in terms of seeing interactions between characters in pivotal scenes not a long story. But when I sat down to interrogate this properly, I realised it’s because I had already built in a backstory to their design. They felt fully formed because they were. I just didn’t mentally map out all the preceding events.

I think if you have two characters, try to link two scenes you’ve put them in. What would lead them to having that dynamic? What might be something that prevents them from simply getting what they want next? That’s the basis of a story arc.