This means they will not have any rights (including access to user portal) granted by default, and these rights or role memberships must be manually assigned.
Also, a Service User account will NOT be listed in the default Set filter view in the user listings, which is named 'All Users Except Service Users'
A Service User account will be listed under 'All Service Users' or 'All Users' Set filters in the user listings.
Please note that you cannot assign the'Everybody' role to a user by design. This is an automatically assigned role.
SDS IAM & EMM
[Summary]
What does 'Is Service User' used for in the Samsung SDS IAM & EMM Admin console?
[Resolution]
By default, during a new user creation, the 'Is Service User' box is 'unchecked', so the user to belongs to the 'Everybody' role.
If the 'Is Service User' box is checked for a user, then this user will not be a part of any roles, including 'Everybody'role.