Its adds a certain mystery and mistique to the character and villain. The not knowing is what attracts us to him and makes us fans fall in love with him. Plus the mystery of who The Joker really is is what draws people to the movies in hopes of cracking the mystery but the mystery is never revealed. Keeps us craving more. THE JOKER WILL REVEAL HIMSELF WHEN HE WANTS TO. He is one of the most prolific iconic bad asses in all of comic history. Cant wait until Suicide Squad comes out. Jared Leto is gonna kick some major ass in the role. Super excited!