The other day, while driving home, I encountered a (thankfully empty) 5-gallon plastic bucket which was bouncing around in the middle of the 5-lane interstate I was on. Actually, my car encountered it, and it bent my front passenger-side fender. It would have done more damager, perhaps taking out a headlight, except that I did a minor swerve at the last instant to avoid a more direct collision. I would have moved to another lane but there were cars on both sides of me.
I got lucky, and the damage could have been worse. And if it had been some little old lady (for example) who swerved wildly to avoid this obstacle, a massive vehicle wreck might have resulted.
Simply put: this bucket fell off of SOMEBODY'S truck, because it wasn't properly secured. In an ideal world, people responsible for things like this would be taken aside and beaten severely, to ensure that they learned their lesson and didn't screw up again.
You may like my stories, but believe me, you wouldn't like me as the king of the world.