(Don't get me started about flash fiction, i.e. a story less than 1K words. It's a talent I haven't mastered, and mad respect to those who have.)
It's been a while since I've written the shorter forms, so my skills are a little rusty. A writer still needs descriptions and strong characters, but there's fewer words to drag a reader into the story. The genre and editor requirements make a difference.
There was a time I was a natural short form writer, but I was leaving a lot of stuff out that would make my work a better story. In fact, a couple of published author friends said I was writing screenplays, not novels.
But the freedom of being indie is that I don't have to force my stories into particular boxes. I finish the first draft. I edit it. I send it off to my alpha reader. That's it. Whatever the final word count is only matters when I go to make a print version. If it's a short story, I'll publish it as an e-book, and then I'll decide to group stories of a particular theme or by characters and group theme into a an anthology. For example, the Bloodlines short stories and novellas are collected in one paperback.
Unfortunately, when an editor contacts you with an invitation to write a story for them, they have a specific genre, word count, and theme already decided. I have to force a story into their dimensions, which for me is pretty damn difficult. And frankly, it scares me a little bit.
But if it scares me, then I need to do it. That's part of growing in our art.