Why can an employee perform a task in a journey even if he is not a performer?

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Hi everyone,
we configured a checklist where the first task in the journey has the worker as the performer, and the second task has the Human Resource Representative as the performer.

The performer of the second task is specifically configured based on the responsibility area, which the worker does not have. This is not the expective behaviour. Therefore, we are wondering how it is possible that in this case the worker can receive the Human Resource Representative’s task and complete it.
Is it perhaps because the task owner is the initiator and is the same as the worker?