Reason #5: I'll Just Pad This Out

Elmore Leonard's Ten Rules of Writing, #10: "Try to leave out the parts that readers tend to skip."

Padding: When you run out of ideas, but keep on writing. It's also something insecure rockstars do to their crotches. The fluff covering the flaccid.

There are only two reasons to pad your writing:

You've got a target wordcount and a deadline you can't meet

You're bored/stuck with the section you're working on, so you digress

They both equate to:

You have contempt for your readers.

If your story is short on wordcount, that's because it's a short story.