In the Olympic Games there's a temptation to measure greatness by the number of medals won. This carries a bias towards those who enter many events and do well in most or all of them. On the other hand, there are those who enter only one event because that's what they specialise in, or that's all that's available. And among those athletes, those who came back Olympiad after Olympiad and keep on winning their one gold. Think Steve Redgrave or Al Oerter.