When all is said and done, it’s your book. You are the last word on how your book turns out when the whole process is finished, which includes the editing.
This editor recommends going over your book and checking all the edits made once you get it back, to decide which ones to keep and which ones to reject. Because they are all your words. And editing, with fiction especially, can sometimes be subjective.
That being said…
If your editor has made a change to your manuscript, they had a reason for doing so other than just to make changes or because they like the color red. Very carefully consider the change and decide with caution. Consider why you don’t want to keep it and make sure your reason to not keep the alteration isn’t just ego. Because we all have them–editors too! So, think it through before you decide.
After all, if a book goes out that looks like it wasn’t edited, it reflects on us both!