Proximity effect. Unless you are an astronaut, you probably never considered taking any practical action to avoid being ejected into outer space. In fact, the things on your mind most to try to avoid from happening are going to be the things that your mind notes as being most immediately dangerous. For example, places like Florida have special building codes to make buildings more resilient against hurricane damage. Buildings in Vermont have special building codes to make sure that they can withstand a deep frost line. Everything is usually hunky-dory, but, if a hurricane hits Vermont, even if it's a little piddly one, it wreaks absolute havok on homes and businesses, as was the case with Irene a few years ago. Likewise, if Florida were to ever have a Vermont winter, the buildings there would crumble apart from the frost. So, people spend the most effort and brainpower on problems that are assessed to be likely situations. You build a 401k so you won't starve out on the streets homeless after retirement, yet, you probably didn't consider spending the same amount of money building a death-ray in case extra terrestrial aliens immune to conventional weapons invade the Earth in order to eat everyone.