While it is difficult to generalise about the decision making process used by British and American universities - universities, regardless of location, give priority and weight to different factors- it is fair comment to say that there are significant differences between the two systems. At the end of the day, of course, both systems are trying to admit students who will be able to thrive and prosper in their particular educational setting. The American system, however, takes a broader, more holistic approach to the admission process.
US Admissions Officers often talk about “The Match”. By this they mean that, while not seeking to accept “identi-kit” applicants or clones, they are seeking to accept students who will be able to take full advantage of the educational experience on offer and who will be in a position to make a contribution back to the institution. To accomplish this, American universities, again, endeavour to look at the “whole person”, not simply the “academic person”. Though universities are, of course, clearly about academics, “learning” can be experienced in many areas, not just sitting in a classroom.