Today, as I was about to send the images of our invitations to the printer, Jon mentioned that I should ask cc (as in COPY chief) to give them a once over for any errors.
On one of the insert cards for a secondary event, I had arranged all the letters perfectly to spell out who it was for, what it was, where it was, what time it started and what time it ended. Cc gently pointed out that I had left off the FRICKING DATE. I cannot imagine my mortification if they had gone out that way. I know, there are way bigger problems in the world than that, but when you're running around correcting people all the time, it's hard to play it off when you've missed something that big yourself.
Plus it became clear that I've been sending all Birthday, Mother's Day, Christmas correspondence to my godmother with the incorrect postal code on it for more than 20 years.
I'll say it again, though I've said it eleventybazillion times: everyone needs a copyeditor.