A conversation from the mid '90s that made me realize why announcers have to repeat things so often:
Co-worker: I heard you on the air yesterday while I was driving. You were promoting a concert for...Who was it? For some reason, I want to say Poppin' Fresh...
Me: That's the Pillsbury mascot. I'm trying to think of which concert promo you might have heard.
Co-worker: No, it was for The Poppingtons. No, The Rippingtons.
Me: The Rippingtons...That's right.
It dawned on me that this must be why announcers repeat the same information, such as a phone number, a store location, or a price, so many times in a commercial. It's one thing to expect people to retain all of the necessary information after one hearing as part of a job or when taking a class. It isn't realistic, though, to expect every listener to remember everything you've said when they're listening to a radio station passively, by choice.