Cloud technologies profit basically from the so called all independent concept. It means a cooperation of many computers, disk arrays, server network switches, and many other elements collectively called nodes.
When some node is not available, the rest of the nodes fully cover its absence. In such moments the whole system must not be unstable or it could go down.
To build such an environment in-house leads to an overkill of expenses. Years ago big players came with an offer to provide fully supported services using the cloud concept. It reduces the expense IT solutions because hardware and software are maintained by the provider, and the customer always pays just for the feature and performance level they need. One of the most basic properties of every tenancy is pay-as-you-go charging mode, which enables to pause, stop...