We definitely know why that nose is so important!
Not really a fan of clowns? As it turns out, the red makes the nose stand out and look comically larger when up against the white makeup on the rest of the face. Is there something about red that is much funnier than purple, orange, or even green? Just flick on the switch and not only will you have a giant red ball for a nose, but it will also light up for an even more fun look.