There was a known issue that was recently resolved which made it so that personal tasks would show up on your timesheet:
https://experienceleague.adobe.com/docs/workfront-known-issues/issues/new-workfront-experience/wf-cu...
I actually thought this was great for tracking time of non-project related administrative work such as annual trainings, reviewing resumes, etc.
It would be great if there were a timesheet setting that allowed an admin to either show or hide personal tasks!