I was thinking the same.

Normally when you see the sign you just see “nothing” or “impossible” . But only on certain angle you see “nothing is impossible” , implying something that looks impossible is not impossible just look at it from a different angle.

Which is fun, but still people who are driving by and just see one side, or see that sign just one side from their window all the time, and are mildly depressed, might not appreciate it.