Or you're like me, and you panic, thinking you somehow slept through the night and it's 8:37 AM, so you sprint around in an adrenaline-fueled frenzy, trying to get ready because you're already super late for work, and why didn't anyone call/wake you up?!?! And then you realize it's dusk outside, and everybody else is home, and you feel stupid.
And that, my friends, is why I use a 24 hour clock now.