Day 1 — The Wider Blade
“People keep plugging it in wrong.”
“Make the unsafe way not fit. One blade is wider, so the plug only seats the right way around.”
Wait, really?
North American polarized plugs use a wider neutral blade so a simple appliance cannot swap live and neutral. Same idea as a SIM card’s cut corner or a keyed connector: the wrong orientation is a shape, not a lecture. It does not stop every electrical mistake. It stops one.