Proofreading is a task that is often neglected. I know that many people do not realise the importance of proofreading. To me, a document that is not proofread is unprofessional. If I see a spelling error in an advertisement, I refuse, on principle, to have anything to do with that business – it shows me that they do not care enough to make sure that what they are presenting to the public is professional, and it is a bad reflection on their business. That business’ un-proofread document/advert/signage has lost this customer (and how many others?)!!