Goals: Notes visibility options

Summary

Difference between the 'Managers Only' and 'Managers and the worker'

Content

Hi, 

I am wondering why it is relevant for a worker and what is the difference between the 'Managers Only' and 'Managers and XY worker' visibility option when we add Notes to a goal. I understand it is important from the managers perspective. 
If there is really no difference between these two options, there is any way to hide it from the worker's side and keep it on the manager's? 

Thank you,
Dora