[jappgar]

Because it's funny?

Life would be pretty boring if everything were explicit.

Also, sometimes explaining the rationale for a warning can backfire.

An "absolutely no smoking" sign at a fuel depot doesnt tell you _why_ you shouldn't smoke there... If it did, dumb people might think "We'll I'm not refueling at the moment so it will be fine."

"Here be dragons" is vague for a reason.

[martinflack]

I've lived in the US and UK and noticed what I think is a tiny cultural difference -- that signs giving instructions in the US tend to be brief and contain the instruction only; whereas in the UK I thought I saw more that add some text for a brief explanation or reason, if it wasn't obvious.

[Gud]

In the UK they love their safety labels. Only country where I’ve been where there’s a safety label on everything. It’s ridiculous.