The advent of cloud has all but eliminated the limitations provided by each of the preceding points. Cloud providers now completely manage the undifferentiated heavy lifting for their customers. They've bought the physical space to house the data centers; deployed network, electric, and cooling systems to support millions of machines; managed security of the physical infrastructure, performed background checks, and segregated duties to ensure that no staff has both physical and logical access to systems; designed and deployed state-of-the-art cooling systems; and have a staff of focused operations engineers to maintain their massive fleets of data centers. For a further discussion on the cloud providers' scale, please refer to Chapter 13, Scalable and Available.
In every one of these points, the CSPs aggregate and reduce costs through economies of scale. A company such as AWS or Azure can spend more time designing more secure systems than other enterprises because they have...