I swear to God, and you can probably find a post from me about it in the past, but I almost wrecked my car from laughing when my wife had the same disconnect on our way to Florida many many years ago. "Ohhhhhhhhhhh! So that's what it means! Now it all makes sense!"
I learned never to take anything for granted like that. Every year in physics class, I have a few students who don't understand that - they never learned it. (And are at a stage of increasing logical thinking where they've never really encountered it.)