Question

why is disaster preparedness and training important

Answer 1

This is because disasters are not bizarre anomalies, they are natural, normal events. Tornados, earthquakes, Floods, etc. happen because that is how the earth "works". And, in a similar way, intentional and accidental infrastructure failures (power grid collapse are one example) are inevitable consequence of humans' nature as fallible creatures.

So do not be one of the many dazed and helpless victims of the next inevitable, normal bad turn of events. Become one of those who understand and expect disasters to happen because that is just how the world works. Be ready to calmly manage whatever comes, and to help your dazed, helpless neighbors and coworkers. They will need you.