By default, the progression of a Deliverable follows the Workflow illustrated below:
By default the Default Permissions (users allowed to read or write the object) and the Default Responsibles (users responsible for moving an object from one state to another) are set to all users at the Workflow level.
Upon any transition, the user will be prompted to enter comments in a popup. These comments will then be available for review in the Workflow Information dialog box.
Settings
Comments will be disabled if the Enable Deliverables Workflow Comments option available in the System Settings workspace, Work Management Settings folder, Work Items tab is switched off.