Given a system with static permissions (1 permission for every action that can be made: create a resource, update a resource, etc), and dynamic roles (can be created and assign permissions to it dynamically).
The system have a preconfigured set of roles with the purpose of initial setup and/or testing. These can be deleted or modified after the initial setup, hence "dynamic".
When acting as a user with one of these preconfigured roles on a [functional/acceptance] test to assert a use case works properly, do tests that assert a user with a role that does not have the permission to execute that use case have any value?