You have observed it many times around you during the elections or in the companies. People have seen themselves as winners of a position well before they have got it. They have promised their companions share on the future fruits of power. They have started to behave in their natural (arrogant) way being so sure they do not have to pretend anymore. They have overestimated their previous success and influence. They have seen things as they wanted them to be, not as they were.
The more sure they were about themselves the more harsh was the next day awakening into failure. They felt as victims of conspiracy. They felt it is not fair to them. Why it has to happen to them, when they have already lived their dream of a conqueror.