How does VM restart priority works?
VM restart priority determines the relative order in which virtual machines are restarted after a host failure. Such virtual machines with the highest priority are restarted first and continuing to those with lower priority until all virtual machines are restarted or no more cluster resources are available. If the number of hosts failures exceeds what admission control permits, the virtual machines with lower priority might not be restarted until more resources become available. Virtual machines are restarted on the failover host, if one is specified.