“Be careful!” No, really, I plan to be deliberately reckless as I drive home/ carry something fragile/ walk across an icy parking lot/ use a sharp knife/ pour hot wax. It’s even more annoying if I have stubbed my toed or something like that. Because, yeah, telling me to be careful after the fact is so very helpful.
Seemingly everyone says it because it is the socially acceptable thing to say. However, has anyone ever defined what “a nice day” really is? Besides, what if someone wants to have (or is already having) a completely horrible, awful, dysfunctional day?