There's no such thing as a perfect manuscript.
(sorry, long-winded editing talk that's only interesting to me, feel free to ignore me! )

But really, there isn't. I see a lot of "I hired an editor and still found errors" or "they should have hired an editor" comments; (cont)

But good, reliable editors never guarantee a perfect manuscript. That'd be a blatant lie and career-icidal.

With a big publisher, you'd have four, five, sometimes more editors and proofreaders running through your work, and still there's a small expected rate of errors.

Editing is expensive.
So if you're an indie and hire just one person to do developmental editing, line editing, and proofreading on your four hundred page manuscript all by themselves, it's totally understandable!
...but definitely not gonna be perfect!
...and that's okay!

With a good editorial relationship, what it will be is SIGNIFICANTLY AND VISIBLY better than it was. That's it, that's the goal.

Ideal result, you go "Whoa. That's SO much better! I sound great! And learned so much! Oof, what a weight off my shoulders."

As for "they should have hired an editor" comments, (note, I am NOT talking about reviewers saying they were tripped up, I am referring *exclusively* to us writers snarking about each other), when I see someone make those, I immediately open up their sample.

... nuff said.