I saw this on the back of a truck yesterday which left me perplexed...

Warning: This vehicle in constant forward or reversing motion.

Since when do you need to warn someone that a vehicle moves forwards and backwards. My car does, I don't have a warning label - I thought vehicles were supposed to move forwards and backwards. Isn't that why you have a vehicle in the first place? So it can take you places? Irrespective of whether it does it backwards or forwards?