it should be the first athlete to ENTIRELY cross the line a) Why entirely across, and not just the first to touch the line? b) I get that basing it on the who

it should be the first athlete to ENTIRELY cross the line a) Why entirely across, and not just the first to touch the line? b) I get that basing it on the whole body feels a bit more objective, but it would probably also lead to people diving over the line to gain a few milliseconds. As well as looking a bit silly it could be dangerous. The lean through a (now virtual) tape at chest height is traditional.