I think a lot of people fell for the Boris effect. He is engaging but was never to be trusted, and effectively destroyed his own party. The man is a hell of a campaigner but he can only lead by rushing to the front of crowd.
He played a lot of voters. Ruffled hair and stutters for the cameras and jolly japes. The man can speak perfect Italian and Greek, calls himself Alex and combs his hair quite well in private. Old Tories absolutely knew he was full of it