I too contemplate these questions, but my questions are questions of "firsts." For example, who was the first person to think a Durian would be a good thing to eat. If the weapon like exterior didn't look inviting enough the putrid smell should have detoured any further advances.

Perhaps the first encounter with said fruit was not as destructive and violent. It could, and probably was, a chance encounter while wandering through the forest and finding these objects on the floor. However I would have thought the smell would stop any normal person from deeper inspection. The wise comedian Demitri Martin once stated that "whenever we investigate smells it's always something nasty, it's never,'What's that smell? OH! Cookies!'" Resonating with that idea, why would you, upon discovering the smell was not in fact cookies continue to the point of thinking of "even though this smells gross I wonder what it taste like?" A normal reaction to strong and offensive smells is not to try and see if it taste good but to throw it out, which in the case of durian may have resulted in yet another head injury.
I like to think that durian and it's acceptance as a edible treat is proof that though alcohol did not exist in early human history, since the beginning of time "Truth or Dare" and like games have played a major role in culture as well as the idea that our ancestors must have been as dumb or dumber than we are to have tried things which defy logic. Here's to you, durian and the bravely stupid person who first tried to eat you.