Voldemort, as we all know, went beyond "usual evil" when it came to his soul. In making so many Horcruxes, he made the remaining bit of his soul very unstable. This also altered his appearance. Of course, we can't discount his प्यार of snakes. Thus, he would want to look like one.
How i've always imagined it is as follows: It's something like a reverse Pinocchio effect. The और evil he became, the shorter his nose got. Until one day, it was completely gone. And his goal at being inhuman was now complete. The end.
He was in the car with his parents when they crashed into a crocodile. His parents got eaten but then the मगरमच्छ took out a चाकू and cut off his nose.
Maybe voldemort's curse hit it leads to his nose... but I wonder, when still tom riddle, his nose was fine, but why voldemort's nose missing? Pug.... hahaha...! i'll say it loud! hahaha!!!!
A game of 'got your nose' between Voldemort and Dumbledore got out of hand. OR Bellatrix wanted a part of Voldemort all to herself so she took his nose.
One दिन in Percy Jackson Land, Voldemort was in the WRONG STORY. Percy came up to him and chopped off his nose because he thought he was Kronos and thought maybe this would be his new Achilles Spot. But it wasn't and Voldy just got mad. The end.
Personally I think that when he reformed the ingredients that was used to make him made his aperience like that या maybe it was because since he लॉस्ट his powers to a baby people would think that he died and isn't alive anymore Voldemort wanted his aperience to look scary so people would fear him once again
It was stated in one of the books, when Dumbledore was talking to Harry, that Voldemort was part snake (I think b/c the whole horcrux thing with him & Harry being similar) so I think that's why he has no nose