I just figured out why so many people at my office are so annoying: they're mostly former teachers who have carried over their teaching personae into their administrative jobs. I think most people adopt some sort of teaching personae when they're in the classroom, whether that's a little nicer than you actually are, your most professional self and/or the person with infinite patience. Sometimes the personae is quite different from the actual person and sometimes it's a minor variation.
I think the people in my office, particularly the people in my cubicle, have adopted their teaching personae as their professional personae in general. They use cutesy voices to talk on the phone and address groups of people that might have been appropriate in the elementary school classrooms but comes across as condescending when they talk to other adults.
Anyway, it drives me kind of nuts. I know that's silly and petty, but it does. So there.