There are lots of reasons why you might decide to run important documents, publicity material or even your webpage content past a proof-reader. One of my clients is mildly dyslexic and so likes to make sure he hasn’t made any glaring errors; another client doesn’t have English as a first language. Sometimes it is just a matter of correcting mistakes – if you’ve written and subsequently edited a piece of writing, you will often miss small errors that have crept in because you are too familiar with the material.
In my opinion, however, one of the strongest arguments for using a proof-reader is clarity of communication. You have something to say, you know what you want to say so you write it down and it makes perfect sense. Of course it does. Except that the person reading it hasn’t got the same insight as you do and what might seem crystal clear to you may not be quite so obvious to someone else. This can be the case if you have specialist or technical knowledge of your subject but are writing for a non-specialist audience, or it can just be a matter of ambiguity. For example:
“An Account Manager is assigned to each client with a good working knowledge of the relevant systems.”
An independent proof-reader can look at your material objectively, point out areas where clarification is needed for the reader and make suggestions on how the material could be improved. Content that has no mistakes and is easier to read becomes more accessible, more client-friendly and improves your professional image.