You can set goals for your employees, or have them set their own goals through the Goal setting feature present for both persons and teams.
To access this, go to either the Person or Team listing from the left menu and click on the Goals icon in these sections. Then you can set goals for these employees both individually and as a group.
Once you have evaluated these goals and want to have them shown as completed rather than deleted for future reference, you can hit the Complete goal icon on the Goal setting page. This will clear the goal from this page and it will now show up on the Completed goals page.
You can restore the goal from here in the future if you wish to. You can also set due dates on goals so that employees can achieve their targets in a timely fashion. Once completed, a goal will not count towards future evaluations unless restored back.