Dave: Why do you fail to grasp the reality of who goes/stays?
It's really pretty simple. If a fighter can make money for the UFC, he stays. If the UFC will lose money on him, he goes.
Sell tickets, whether by winning, talking crap, being exciting, etc. and you'll keep your job. If you're boring and people don't want to pay to watch you fight, you're gone.
UFC is a business and when it comes to MMA, they do it best. Don't expect them to change because of some guideline you think they should follow.