IMO what we should be doing is 'selling failure' to the decision makers. We know the systems will fail at some point, somehow. The key is to know how systems will cope with failure (graceful or with a bang), how you can recover from that, how long that will take and how much that will cost. That can then be balanced against the cost to the business of such a failure.
I have a building on our campus that could provide a home to equipment & give us some 'offsite' capability, but how far do you go in considering a disaster? A fire or flood in the server room (Sprinklers in a server room not a good idea) is one thing; getting Senior Management to consider a disaster of epic proportions is more challenging..... What about an accident at the top of the school drive which led to a flammable liquid spill flowing down the driveway, entering site surface water drains & catching fire... taking out the whole site?