As a truck driver, I am always questioning the sense some drivers use daily in my travels. I am amazed at the lack of maintenance people put into trailers, especially wheel bearings. I couldnt begin to total the amount of trailers I have seen on the side of the highway with a wheel missing. Yesterday, I saw a pickup, pulling a bass boat that had lost a wheel. I can only guess that when the trailer lost a wheel, the driver lost control. To add more bad luck, it happened right in front of a section of guardrail. The truck struck the start of the rail and it pierced the cab, almost out the back side. The engine was in the back seat. I dont know how the occupant(s) made out. I saw the boat and trailer on the flatbed and the axle was still there, so it appears that wheel simply fell off.