Because if your mining company gets flooded and you can't mine for a few years you have to be able to find new mines or sell you equipment, or even the mine it's self.
-A mine not producing, is a mine that's losing.
You can apply this to almost anything, but it's most prominent in evolution and Business. in Evolution you die, and in business, if you company is losing money it will die so you have to adapt to sudden changes to avoid imminent death.
Hope this helps.
-Trey Tucker