In the context of disaster planning or preparing for a hurricane, a business who is largely operating out of the cloud, or let's just put it, a business who's operating out of the cloud is going to be inherently more resilient than a business who's operating out of an office space. When the office loses power and it's shut down, you can't get into the office.
The batteries, battery backups will die off at some point in time. The generator will run out of gas. At some point it will be shut down and then you're out of business. That's pretty simple to understand.