I have asked this of myself several times. I put a lot of time, effort, and money into stock piling water and other supplies. But what if S**t doesn't hit the fan? Was all that time and resource wasted?
Preparations come in advance of successfully achieving a goal, the lack of preparation comes in advance of failing to achieve a goal. My goal in preparing for a disaster is that I and my family will survive whatever disaster my occur. Failure is not an option!
I feel that if nothing catastrophic happens, great! I have still achieved my goal and if I die of natural causes before SHTF, then I have set an example and left a good start for my family should such an event happen during their lifetime. I am convinced it will. Be it an EMP or a pandemic, nuclear war or massive earthquake, a breakdown of social order or worldwide water shortage. I really could go on, but you get the point.