Because X Factor is a rubbish program promoting the same old, same old in music and is basically glorified karaoke and she woke up one morning, realised this and though 'hey, if I actually have talent then I don't need to use this pile of poo program as a platform and besides strictly come dancing is on the other side and has more class' ?
I washed up before I went to bed!! It's you lot sitting round chatting on your coffee mornings that does it, can you not use the same mug the second time round?!