Hey,
If you power off the node by unexpected power off (not graceful shutdown), cluster can't live migrate the VM. As you have described, it will be booted on the available node. Live migration is not possible, because compute resources of the VM (CPU, RAM) went offline, thus, they cannot be migrated. Failover cluster ensures high availability of the cluster roles.
https://learn.microsoft.com/en-us/troubleshoot/windows-server/high-availability/high-availability-overview
If you want your VM/resource to be always online, you would it to be Fault Tolerant. Might be helpful:
https://www.starwindsoftware.com/best-practices/starwind-virtual-san-best-practices/
Cheers,
Alex Bykvoskyi
StarWind Software
Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.