>>77088826I have this answer.
Stan Lee was the publisher by the 70's, usually dealing with other stuff but occasionally coming by the office. One day he saw an Iron Man cover on the wall and made the comment, "Where's his nose?" He meant that Iron Man's helmet looked took small, there was no room for his nose inside. They took this to mean they should give Iron Man a nose, because if Stan said it, they'd better do it.
Months later when Stan saw another Iron Man cover, he asked why there was a nose on the helmet, because it looked stupid. So they got rid of it right away.
They even had other characters make fun of it.