Life-critical industries like airlines, cars, healthcare, etc. are probably the exception? If a restaurant ran out of some menu item for a few days because a s

Life-critical industries like airlines, cars, healthcare, etc. are probably the exception? If a restaurant ran out of some menu item for a few days because a supplier didn't have a good harvest, eh, it happens. If a bookstore doesn't stock a certain book, no big deal. Grocery store self-checkout broken yet again? Oh well. Band got too drunk and can't perform? Reschedule it. No snow at the slopes? Climate change. In the real world, shit happens, and most of it isn't critical. If you offer a 99.999% guarantee and your customers pay for it, well, you better deliver -- subcontractors or not. But many businesses don't need to do that and a few hours of downtime a year is just a minor inconvenience. To go from "a few days of downtime" to "a few hours" is really easy; just about any provider can offer that. To go from "a few hours of downtime" to "a few seconds" is a huge investment and not worth it to many folks.