[MarcusMel]

He went because nobody thought he would be voted out!
If it was a vote to save Winston would have stayed. The assumption was that nobody was going to vote Winston out so when it was realised that the public could hurt Helen who was protected by the 'pass to the final' Winston became the sacrificial HM to the pass to the finals curse. Also Winston, Ash and Helen had a conversation that 'Winston' was going to win BB and so addad a second set of votes on the gang of people who say 'you must never say you are going to win BB'. (But this may not be so for Pav who has been treated by everyone so badly we should be ashamed to call ourselves human!)

Also it is good for Winston as he now gets extra media cover.