Your Active Directory contains non defualt primary groups.
In A migration Session, you slect users, and use the "select by group membership" option to also migrate groups the user is a member of.
after clicking the "Select by Group Membership" button, you choose "Select Groups for Selected Objects", and checking group all types the users
primary group does not get selected.
This feature Querys the memberof attribute, which does not contain the primary group. A users primary group is stored in the primarygroupid attribute
QMM does not return the primarygroupid attribute.
Primary group is typically Domain Users or Users, which exists in the target allready, and does not generally need to be mirgated.
Manually select primary groups, and migrate them
