Because creating new virtualized servers is so quick and easy, many organizations have a problem with “VM Sprawl”. With VM Sprawl, the number of virtual machines (VM) running in a virtualized infrastructure increases over time, simply because of the ease of creating new VMs, not because those VMs are absolutely necessary for the business.
Concerns with VM sprawl are the overuse of the infrastructure if it is not needed and the cost of licenses for virtual machines that may not have been required.
To prevent VM sprawl, you should more carefully analyze the need for all new VMs and ensure that you are able to justify the cost of the infrastructure and the licenses for all new VMs created.