I remember being confused as a kid by "Yes/No/Cancel" when the computer asked "Do you want to save the changes...?" because I couldn't figure out whether "Cancel" meant "Yes" or "No" and why on earth would one have a third option. I then realized it meant to "cancel" my intention to close the file. I had been confused because I thought it meant to "cancel" the computer's intention to ask me.

Also, I was that obnoxious kid who, after asking someone a yes/no question, used to add "Yes/No/Cancel" (probably to highlight my perceived absurdity of that button).