Why is Mariah Carey's hair so voluptuous?

Like it always looks so volumized and amazing.. its never flat or dull, how does she get it like that? Even when I go to the hair dressers it doesn't look as good as Mariah's :( example a href="http://mariahsource.free.fr/2005/0421_teomparty/1/009.jpg" rel="nofollow"http://mariahsource.free.fr/2005/0421_te…/a