Help with logic in Dining Review project

Hello guys.

This project went seemingly well, I thought, until I was asked to create an admin class for reviewing reviews.

I just don’t get the logic for why I need creating one. Why can’t I define a get point in the upcoming Controller that:
findAllReviewsByStatus (the status which represent Pending reviews)
and then a Put point that

if (approved)
set"reviewToApprove"(approvedStatus)
if(!approved)
set"reviewToApprove"(rejectedStatus)

Please ignore symbols I used there, that was for clarifying my point, not an example of proper syntax.

My question is, what is it that needs to be in an admin class, and why?