How to restrict the automatic change of the proficiency Rating

Summary

How to restrict the automatic change of the proficiency Rating

Content

We have the Career Outlook > Current Role section is enabled and the employee has the visibility to view the competencies for their current tole. After the manager assessment, the Employee can view Target Rating vs Current Rating and in case the current rating is below the target rating, then the "Add Goal" button will be enabled.
This feature is good and employees can add the development goal.
What we noticed here if the employee completes the goal, the current rating for the specific competency is changing to the same as the target rating.