On top of all those very reasonable points, they are building a class. Some characteristic that may be desirable in one, ten or a hundred members of the class m

On top of all those very reasonable points, they are building a class. Some characteristic that may be desirable in one, ten or a hundred members of the class may not be desirable in every member of the class. For example, what if you took in all people who were interested in pursuing degrees in mathematics? The math department doesn't have the facilities to teach all those students and the upper class history classes are going to be empty. It's a matching problem as much or more as it is a ranking problem.