There are two forms of ambition;
1/ The ambition to do the best job possible at any given task. An entirely laudable motive.
2/ The rat-race ambition to 'get on in life'.
Such ambition is almost always inextricably linked to blinkered competitiveness. In addition those who possess high levels of this form of ambition/competitiveness seldom possess anything approaching the same level of ability. All too often they have poorly developed consciences and are disinclined to engage in remedial introspection. Thus we have the confident bluffer.
We live in an age of the confident bluffer. Like the Peter Principle - wherein organisations promote individuals who are competent at their jobs up to the level where they are no longer competent, thus gumming up the organisation with incompetents, the confident bluffers con their way into positions which are beyond them.
In addition to cheating the more able out of their chance, the confident bluffer typically causes endless problems for those who have to work with them, or pick up the pieces after they've gone.
The job of selling is the natural home of the confident bluffer - no surprise then to find politics and advertising packed to bursting with confident bluffers. However when it comes to misplaced confident bluffers nowhere will you find a higher percentage of them than in Fine Art and the media.