My goal as an editor is never to criticize, but to ask questions, suggest, encourage, prod. I believe the best judge of when your piece is finished is you; only you have the dream for the piece, only you know when you've accomplished it.
The problem with dreams though is they can be hard to remember, especially when outside realities start pressing in. When people are telling you what should and shouldn't be included and what is and isn't important, or you're slogging through drafts and revisions, or your own inner-critic starts going crazy with the metaphorical (or maybe literal) red pen...it can be really easy to forget what the heart of a piece was in the first place.
As an editor my goal is to help writers find their way back to that dream. I ask questions where I'm a little confused or where I wonder if there's more there than you've committed to the page. Coming in from above, I make suggestions of what I think you're working toward and which you may be losing track of while hacking away in the thickets. I highlight areas where tangents and rabbit holes might be developing; more importantly I share aspects that really resonate with me. Your dream as a writer is a sacred space to me and I take seriously the honour of being invited in.
Through it all, I have no expectation or even desire for you to take my edits as mandates. In fact in my experiences as an editor and writer have shown the most rewarding moments in the editing process often come in pushback. There've been many times when I wrote A, an editor said it should be B, but after thinking about it, I decided the answer is really C. Sometimes even more powerful have been the times I tried B, C, and D and then realised that the answer was A all along, that I just needed to understand it was a lot more important than I'd thought when I'd been drafting, and that I actually needed to lean even more into it. (And the same has been true when the roles are reversed, and I'm the editor.)
If I'm privileged to work with you, I hope you'll have some of the same joy I've felt when finally having a piece become a dream come true. (You can see the services I'm offering here. You can also note my love of puns here.)
(note: I am forever indebted to my teacher, mentor, and friend, Sheila O'Connor, for - amongst many things - teaching me the importance of protecting the dreamstate we inhabit when writing our truest works)