A sign that we all see and know yet hardly anyone knows the actual reason that vehicles have them.

So it should be fairly obvious not to follow a construction vehicle. I asked a few people why they think you wouldn't and they answer because of the possibility of loose debris flying off the truck and hitting your car. This I know being someone who has worked in the construction field to be wrong. That ultimately would be a safety issue. That is also why those trucks have tarps that will cover the dump body of the vehicle.

The real reason is these vehicles will go into areas you shouldn't. Think of this. In a snow storm we all tend to love it when we have a plow in front of us right? If for some reason you space out a touch behind the wheel, it could be possible you may follow the plow. Same goes for construction vehicles. One second you follow a construction vehicle, next minute you are stuck in inches of thick mud.