Egos - we all have them! They're part of what makes us want authority and status, and what gives us confidence. Egos drive our need to be recognized for our accomplishments. This is perfectly normal.
But what happens when someone's ego goes too far? You know the type: the colleague who will do just about anything to claim credit or gain power; the person who takes over every discussion and tries to grab the spotlight; or the team member who continually criticizes other people's ideas. These people are undermining the team's mission with their behavior.