Wrike Analytics Filter Locks

I have a general question: Why can some report filters be Locked and others can't?

I created a report for a manager that contains only the projects from the employees that report to them directly. I used the "Project Owner" filter to pull in the projects assigned to selected employees. I also have a pie chart "Projects by Owner" to allow them to quickly filter to only 1 person's projects - this is helpful for their 1:1 meetings. 

If they click "Clear Filters" to see all of the projects again, it shows projects assigned to all employees, not just the ones that report to them.

I would like a way to have a filter "locked" in such a way that the user can filter the report using the pie chart widgets, and when they click "clear filters" it resets to the locked filter settings. (I managed to get this filter to "lock" but when I clicked on a name in the pie chart, it set that person in the "locked" filter and I had to click edit, unlock and update the field, so the lock seems quite pointless as it currently works.)