I saw a car (sedan) disabled in the left (driving) lane of a fairly busy road, with the right front wheel off, and the car resting on the brake rotor. The car was new-ish, and in good condition. I only had a brief view as I drove by, but saw no sign of an accident/collision. The tire and wheel (leaning against the side of the car) looked OK.
My question is, what could have happened? They might have had a flat, and then the car fell off the jack while changing it; but, it would be pretty crazy to do that where they were. If the wheel had come off (someone forgot the lug nuts?), it seems like it would have rolled down the road. I am at a loss.