It is still very interesting how a lot of people still struggle to understand that even if we get "realistic" and say that supernatural stuff can't exist, "luck" is still one of the most important factors in being successful in anything. You can have crazy talent and be exceptionally clever and smart, but if bad situations keep happening to you then even an amateur can surpass you in a single moment just because that amateur had the luck of being in the right place at the right moment by mere accident.
Chess masters had to give up matches against vastly inferior opponents just because they suddenly felt they had to go to the bathroom and couldn't hold it in. Hannibal and most of his best generals lost very important battles because their war elephants accidentally rampaged towards their own armies instead of the enemies. The massive Xerxes' persian army lost the war against the divided greeks because a storm destroyed a big portion of their army while they were sailing. Etc.