Default storage class is set to ocs-storagecluster-ceph-rbd.  The ocs-storagecluster-rbd-virtualization storage class has the annotation of:

storageclass.kubevirt.io/is-default-virt-class: 'true'

The ocs-storagecluster-rbd-virtualization should be selected/displayed as the default storage class when selecting Edit of the rootdisk.

Not sure if this defect is in the OCP Console or the OpenShift Virtualization Operator.

4.15.1

When creating a new VM and selecting the "Customize Virtual Machine", Disks, and then Edit for the rootdisk, the Storage Class defaults to ocs-storagecluster-ceph-rbd instead of the ocs-storageclsuter-rbd-virtualization storage class. This creates confusion to the end users because if you don't change it and click Cancel, it will use the ocs-storagecluster-rbd-virtualization storage class. If you don't change it and click Save, the ocs-storagecluster-rbd storage class is used.

1.  Click Customize VirtualMachine
2.  Select Disks from the top menu bar
3.  Click the ellipses to the far right of the rootdisk, click Edit
4.  Scroll down to StorageClass, ocs-storagecluster-ceph-rbd will be displayed/selected.
5.  If you click Save, ocs-storagecluster-ceph-rbd storage class will be used.  If you click Cancel and not make any changes, the ocs-storagecluster-ceph-rbd-virtualization will be used.

See above - step 5.

The ocs-storagecluster-ceph-rbd-virtualization storage class should be displayed/selected as the default.  If the users changes it, the specified storage class should be used.  Otherwise, the ocs-storagecluster-ceph-rbd-virtualization should be used.