For this reason it is worth practicing revision even when publication of the material is not contemplated. I advised writers to practice writing with trivial pieces, and trivial pieces are ideal for practicing revision. If you have not learned the benefits of revision from practicing on pieces that you are relatively indifferent to, you may not be able to apply the knife to a work about which you have strong feelings. I think it is useful to see the original wording along with the revision and to see whole pages of corrections at once. Sometimes, of course, stronger expressions require more words that weaker ones, and brevity of itself is not the goal.
Some writers work by expanding outlines or sketches so that successive drafts contain more words.
But these are not revisions. The revision is what is done to the story once all of its elements are in place. Something is wrong with a revision that does not reduce the word count. One of the editor's jobs is to correct errors in the author's manuscript without doing damage to variations in usage which could reasonably be considered to be literary style and without harming the special voices of narrator and the characters. Since some editors are not so good as others, authors must make every effort to make the manuscript as consistent and as nearly perfect as can be.