“Percentages refer to the number of errors that were in the document before editing. Therefore, if an editor corrects 95% of the errors that exist in a piece, 5% of the errors remain.
This is different than _introducing_ errors. That is considered a grievous offence in publishing.
No, it is not reasonable to expect something to be error free. It is not what humans can do — especially not after a single effort. Computers can’t do it either.
If you step 95% closer to the wall with each step, you will never reach the wall. But the more steps you take, the closer you will get.
If they want perfection, your clients will have to hire more editors, as each will bring them closer to the wall (perfection).”
* Please note that the word “offence” is written as the author intended. Depending on where you live or where you’re from (such as overseas), it can be written with an ‘s’ or a ‘c.’