On a certain project, I (as a Jira Adminstrator) am able to "simplify" a workflow for a Kanban Board by clicking the button (on the Board Configuration Columns page). This demonstrates that all conditions are met for the existing workflow to be simplified (only one project in the filter, all issuetypes use one workflow in the workflow scheme, no non-native conditions/validators/post-functions, and each status has an outgoing transition).
A certain user who is a Project Administrator for this project and a Board Administrator for this board, 'cannot' simplify the same workflow that I can (the 'Simplify' button is greyed-out for her, which I've confirmed by logging-in as her). The Extended Project Administration permission is active for both of us, in the project's Permission Scheme.
Why can I simplify this workflow, but she cannot?