Don't climb a moving bus

I happen to see this incident today near the Velachery bus stop. A guy who was decently dressed tried to climb the bus after it started to move. The bus driver incidentally closed the automatic doors as he stepped right into the last step of the bus. This guy lost his balance and fell abruptly in the road and tumbled over. Luckily for him, he got away with no major injuries. And this being a small road there were no other heavy vehicle that followed. What if he had slipped near the wheels of the bus or if any other heavy vehicle had closely followed. That could have been fatal. From his appearance he seemed to an educated fellow, why can't he think for an extra second and act wisely by not trying such a thing. Please make sure not to board a moving bus at any stage what ever be the situation.