history: I work in a call center that has 4 members on the team and is based on a queue.  Once you finish a call you go to the back of the queue.  On a regular basis I will get off of a call and the others will log out of the queue so I am back to the top again. My coworkers sometimes put more work on me than necessary. Why do you think they do that?
current: They don't want to talk on the phone and can get away with it for a while.
next: That's not fair and probably very frustrating for you. You need to say something to them.