Consider this. Artists often fine-tune their work. Yep, most artists I know let their work set or rest and then go back to view the project with a critical eye. Some have shown paintings in stages or sculptures evolving as the artist adds or chips away. Grabbing a polishing cloth or adding a few strokes makes a lot of difference.
Writing is best done in drafts! I repeat. WRITING IS BEST DONE IN DRAFTS!
Editing is best done in stages. Yes, EDITING IS BEST DONE IN STAGES!!!
Plotters MIGHT NOT need to work on story or characterization in drafts. Thorough plotters probably don’t edit or add needed details. On the other hand, characters can evolve as a story unfolds. One part of the editing process is about changing details or adding them.
There is always the grammar part. Grammar and punctuation can change a reader’s perception. The second or third draft gives a writer chances to involve readers by adding sensory details and replacing lackluster words with stronger ones. With these drafts, writers can delete or move material readers don’t need to know.
Polishing a manuscript is as important as polishing the jewel in a ring or other piece of jewelry. A diamond in the rough might be overlooked, but that same diamond polished will spark desire! Most women think nothing about adding lipstick and fluffing or curling their hair. I absolutely want my grey hidden and my red lipstick for photos!
MaryMarvella 
Ha. This is my most hated part of the writing process, maybe because it’s when I realise how crappy my draft is, and how much I suck at writing. It is a necessary evil though.
Consider your draft a ROUGH DRAFT! It’s supposed to be crappy! Consider it like brainstorming. You need my help. grin!
Editing and revising are opportunities to flesh out your draft.
I have learned to leave the editing aspect of writing to an expert. If I don’t, and wait to do it myself, I am setting myself up for failure and I may never publish my work!
Thank up, Pam! Each of us can do some self-editing. At some point, we need a new set of eyes to catch the errors we missed. Sometimes points we thought were clear, since we knew what we meant, weren’t clear at all.