Archiving the plan just gives the student and the advisor a record of what was recommended to take. It's an electronic version of an in-person advising session between the faculty member and the student. Students can change courses even after the advisement period and don't necessarily have to follow their adviser's recommendations. With the archived plan, the faculty member can say "I told you to take XYZ-123!"
Archiving the plan also removes the "You have one or more advisees who have request a review", as well as removing the Checkmark from the Review Requested column.
If you are having difficulty or you have unanswered questions, please contact the Help Desk through the ITS Service Catalog or call (518) 388-6400.