Grow organizations downward if possible
The relationship-derived virtual properties that support the organization model are calculated in response to relationship signals that travel down the organization tree hierarchy. For example, suppose you:
Add a new root organization to an existing organization hierarchy
Add a new admin or owner to the root organization in an existing organization hierarchy
The relationship signals that trigger relationship-derived virtual property calculation are propagated down to all organizations in the organization hierarchy, and to all the members of the organizations in the hierarchy. This updates their relationship-derived virtual property state.
If there are many thousands of members of the organizations in the hierarchy, such an operation can take a long time to complete. Because of this, it is a best practice to grow organization hierarchies downward, adding new organizations as leaves of an existing hierarchy, and adding new admins and members to the leaves in the hierarchy tree. This is preferable to growing the hierarchy upwards, starting with the leaves, and then growing the hierarchy up towards the root organization.
If you must add a new root to an existing organization hierarchy with many organizations and many members, or add a new admin or owner to an organization near the top of the hierarchy, perform the operations over the command line, using the examples in Manage organizations over REST.