At the time of the CBB5 race row, a Daily Mail journalist wrote a piece describing her experience of auditioning for Big Brother (during the auditions for BB8). (I DO NOT read Daily Mail by the way, just googled it). The producers warned her of how life in the BB house would be. That most of the contestents who said they enjoyed their time were lying and it's actually stressful and boring 90% of the time. I wasn't hugely surprised reading it to be honest.
http://www.dailymail.co.uk/femail/ar...k-reality.html