You want to be viewed as a team player at work—not a pushover. Agreeing to take on more and more, even when you are already overwhelmed, is a sure way to burn out, and your work will suffer.
Follow these tips to put an end to the behavior:
Take baby steps. If you have been a chronic people pleaser, you likely won’t be able to change overnight. Even if you have the willpower to do that, your co-workers and boss could be taken aback by your sudden use of “No.” Take it slow and make small, but steady, changes.
Stop immediately saying “Yes.” Team players step in and help out when they are needed, but that doesn’t mean you should say “Yes” to everything that is asked of you. Commit when you have the time to do so. Otherwise, be honest, and say, “I just don’t have the time right now,” and leave it at that.
Negotiate. If you truly want to help, do so, but make some concessions. For example, ask for a change in deadline or the scope of help you offer.
— Adapted from “Five Ways to Stop Being a People Pleaser at Work,” Brinda Dasgupta, Economic Times, http://economictimes.indiatimes.com.