Why are Employee and Manager able to add goals to the Performance Document even after Evaluation???

Summary:

Hi friendly experts,

I set up the performance evaluation flow as follows:

1) Set Goals

2) Self Evaluation and Manager Evaluation in Parallel

3) Employee Final Comments

4) Manager Final Comments

After step 2 both manager and employee shouldn't have had the ability to add further goals to the document (not considering Return to worker or any HR action to move the document back)

However, I see that even in steps 3 and 4 in fact even after the document is 'completed' the +Add button inside the Goals section is still active both for the Manager as well as the Employee.

Could you please help me understand why this could be happening?