One of the main advantages of desktop virtualization technology is

High availability and resource scalability.

You can have more than one physical computer as a hardware running as available for the virtual machine. In other words, if a physical computer goes down the virtual machine can continue to operate on another computer in that cluster complete transparent to the virtualized machine.

You can also provide more processing power on demand for individual virtual machines. This allows you to have a large group of virtual machines to share a finite amount of physical hardware in an economic manner.