> Most Fields medalists these days are very close to exceeding 40 years They are usually spotted at a much younger age, and they get the medal when they are al

> Most Fields medalists these days are very close to exceeding 40 years They are usually spotted at a much younger age, and they get the medal when they are almost 40 because after that it will be too late. I.e. if there are several deserving mathematicians you give the medal to the one where the clock is about to run out, since the others will have more shots at it.