Getting rejected or passed over for a promotion that you've been promised for years is always going to leave a bad taste in your mouth. You might believe the words of your employer when they tell you that your efforts will one day lead you to a higher role. And, yet, every time the opportunity presents itself to promote you, they go with someone else, and you're faced with that, no matter what their intentions might have initially been, they're dangling a carrot on a stick out in front of you t…