I have written a little bit about errors in editing before, but this article by my colleague Erin Brenner of Right Touch Editing says everything that I would say about the issue.
Another reason editing can’t be perfect is the simple fact that editors are as human as writers and designers and every other person on our planet. Even though we’re trained and practiced at finding errors, we do miss them. And we’ll miss more of them when there are a lot of errors in the manuscript. Catching more errors might mean taking another pass through the document, which could mean more time and more expense. A good editor keeps your timeline and budget in mind when trying to make the manuscript the best it can be.
Read the full article here.
LibroEditing proofreading, editing, transcription, localisation 
Carl D'Agostino
October 28, 2021 at 12:36 pm
I used to get numerous requests to review a book by a new author. Most of them had so many grammatical or factual errors that I stopped reading at the first chapter. I then emailed a list of errors for the first chapter’s pages and suggested corrections to the author and declined to make a public review. No need to crush an author’s attempt out of kindness. I would also suggest they stop production and publication immediately. Sometimes they would reply questioning my assertions as their editor or proofreader already reviewed and corrected the text. I replied not to be mad at me but confront their “editor”. I replied suggesting they get a refund for alleged editing fees. I am not a published author, editor or professional proofreader but my experience as a high school history teacher for 34 years enabled me to catch so many of these glaring errors as I’ve read thousands of student essays and term papers. I used to sit with students one-on-one and make personal reviews as we read together. I then had them rewrite so I could give a better grade. Their learning was more important than expecting artful and perfect manuscripts.
LikeLike