When selfishness at work and in your career can be a good thing:
Bottom Line: How often do you find yourself being more than just a "team player"? If you find that frequently you're not just assisting with projects of others but outright are doing their work – you're probably not selfish enough at work – this based new research from the Harvard Business Review.
The lead researchers/professors found that there is a very real condition they referred to as "generosity burnout". This occurs when someone is stretched too thin to successfully complete their work effectively in addition offering the level of assistance that some of the others they work with may have become accustomed to you doing. As part of the review researchers found that at first your added assistance is appreciated. Overtime it becomes expected – at least by your co-workers and even potentially your employer. Instead it's best to focus on your best performance for your work and assisting with others only when your work has been completed and there's a real need.