Then you could get all flustered about the fact that you screwed up making it private while I yelled about how everyone is a backstabbing bastard and friendships would be ruined, futures would be condemned, and we'd all end up in some kind of hate-spat that would last until some other ridiculous mishap. You know, like every movie aimed at teens, ever.
Also because it would make you look like you weren't INTENTIONALLY trying to piss me off, but whatever.