What operation/permission that each role "Can't" have or do

On the current JIRA Service Desk permission documentation page below, we could get the information of what each role can do on a Service Desk project, but sometimes readers could have a conclusion from the information on the page that it includes other operation/permission as well. Hence, it would great if the documetation also stated on what operation/permission "Can't" have or do on a Service Desk project.

• https://confluence.atlassian.com/display/SERVICEDESK/JIRA+Service+Desk+permissions