His father used to bully him about his appearance when he was a young child, maybe that explains Jacko's obsession with altering his appearance. If you watch some of his music videos he looked to transform himself into something else, the Moonwalker movie for example.
which was a point i was trying to make earlier that his dad teased him about the way he lookd i read somewhere that he'd even wash in the dark and wouldnt look at himself it was that bad