I think OP's point was that the governing boards don't want the people with the top n grades. They want certain people, and by making the admissions criteria fuzzy, they can pick and choose those certain people and then say "well, our admission criteria is subjective," and "we are looking for 'well rounded people," and all kinds of other vague weasely ways to let them legitimately shape the student body in the way they want.

See also: "Cultural fit" when hiring.