The negative comparison activates deep-seated feelings of unworthiness and inadequacy and can create self-fulfilling patterns in the group, resulting in unhappy and frustrating experiences for everyone. If you observe in yourself or in your co-worker:
Sudden criticism and signs of intolerance
Rivalry, competition, need to win, achieve, impress
Withdrawal, depression, loss of interest
Evidence of feelings of inadequacy, incompetence, worthlessness, inferiority, jealousy
Panic, helplessness, impotence, powerlessness
Obsessive behaviour
Anger, resentment, hostility
Sudden interest in acquiring skills, attending courses