Private Notes, found under Employee Profile > Notes, are only visible to the Team Manager, Read-only Manager and the account Administrator.
When an Administrator adds a note, they have the option to make their new note visible to Managers. By default, this is checked. If unchecked, the note is only visible to Administrators.
Notes added by Managers are visible to Administrators who also have permission to edit and delete the note.
ALL notes are not visible to employees.