the blue shell

[Takahashi2212]

Since the courses in Mario Kart 64 aren't rendered at once, but rather as it is gotten to, having one person all the way in front would mean they would have to render later portions of the track while the other racers are forcing a different part of the track to be rendered, along with the extra background stuff on tracks, items boxes, racers, and the items themselves.

Although this is just an assumption based on what I know, it might be wrong.