Most of society's ills are due to overpopulation, and although humanity tries to keep population levels in check by engaging in wars and acts of stupidity, nature sometimes has to lend a hand when human pestilence begins to overwhelm the planet.
Nothing puts out the unwelcome mat with quite the same panache as a volcanic explosion. When nature wants to bring out the big guns and get rid of as many humans as possible, she sends a super volcano to deliver the message that humans may have committed the social faux pas of overstaying their welcome. Currently, there are six known active super volcanoes waiting for the proper time to rid the world of a portion of its planetary pests.
Avoiding areas known to harbor super volcanoes may or may not increase the life expectancy of the average human. Other natural disasters are lying in wait to assist in the volcanoes in their extermination efforts.