The Base Package Controls One User, One User Group, And Many Application Services

When the system is initially installed, the following information is delivered:

Note: An implementation may use the User Enable setting on the user record to disable SYSUSER so that it is not available as a valid user in the application.

When you receive an upgrade:

CAUTION:
Important! You cannot change or remove the information delivered for ALL_​​SERVICES. This information is owned by the base package. It is provided so that an "initial user" has access to the entire system and can setup user groups and users as per your organization's business requirements. It is not recommended to provide your own users with access to the ALL_​​SERVICES user group. Rather, create user groups that are appropriate for the organization's business requirements and define user access to these user groups. If you introduce new transactions, configure them for the appropriate custom user groups.