Virtualization keeps the systems isolated from each other and prevents conflicts, even though they are running on the same physical server. This means that although your company might only own one or two physical servers, it can easily be running two or three times as many virtual servers.
This way the added advantage of network security intensifies by isolating multiple systems on different virtual servers.
Virtualization leads to more cost savings on hardware, since multiple physical servers are not needed when multiple virtual servers will perform the same tasks, and also by ensuring that your company is getting the most of out their hardware.
Likewise, virtualization assists in maintaining uptime in the event of a hardware failure.