In the fairly recent past, going from an idea to execution of building a software application was a costly and time-consuming business. As a first step, you needed to acquire physical servers and a proper facility to install them. Then, you had to purchase operating system licenses, and licenses for third-party software products. To provide high availability, you needed to install redundant servers, and purchase expensive network appliances. You also had to secure, patch, and maintain this hardware. To protect the application against major outages (which could be caused by an event as simple as an electricity service interruption), you had to duplicate the same hardware and software installations in a secondary location. Additionally, you had to purchase a public IP address, and pay an internet provider for the network bandwidth. And if your application's user base grew, scaling it out meant a lot of additional expenses and required months of planning.
You can see how...
