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:
They both equate to:
If your story is short on wordcount, that’s because it’s a short story.

Absolutely essential rule, 99.99% of the crap you see online or anywhere else could be eliminated by following this rule.
Write your material. Rewrite it. Then cut out everything that’s crap. Then cut out everything that’s only moderately good. Then cut out anything that isn’t top-notch. By that point you’ll probably need to start writing it again – congratulations! You’ve just saved your readers a ton of time!
If you block your book out properly and write a detailed storyboard (mine was 30 A4 pages) first and stick to it, you find you don’t need to pad anything out. However you do have to watch for it.
I was guilty of over-writing, a similar problem, but once this was pointed out to me I have worked to overcome it. So I have LEARNED something and am now a better writer for it.
so ‘Check’