The right sign

So it happened this weekend -- as it does to all Australians at some point in their life (and perhaps elsewhere, who knows) -- the 6 year old noticed the sign to the left. He said "you know that When Wet sign." Yes "It's impossible. The tire marks can't go that way." Absolutely. Many of us have pondered that at some time in our lives.

I think when it comes down to it, it is not clear why the sign isn't like this.

Although, come to think of it, it isn't as dramatic. So the impossible catches attention whereas the possible doesn't.