As individuals seek success, destructive interpersonal clashes can emerge when they believe they can only succeed at the expense of others. Prior work suggests this zero-sum construal of success is more likely occur when people receive negative feedback regarding their achievement. In the present research, we identify another element in the workplace that can strengthen zero-sum beliefs, and not just for those who receive negative feedback, but even for those who receive positive feedback. We propose feedback that compares recipients’ performance to others can lead recipients’ to believe that their coworkers’ achievement is the benchmark for them to surpass, and accordingly, their own success means coworkers’ failure (and vice versa). Supporting our proposition, we find, in both experimental and real-world organizational settings, that feedback involving a comparative evaluation results in zero-sum view of success in the workplace. This effect emerges for both those who receive negative feedback (i.e., people who have lost) and those who receive positive feedback (i.e., people who have won). Moreover, it remains robust when controlling for various individual differences discussed in past research. Finally, we find that when people recall emotional and practical support from their coworkers, comparative evaluations exert significantly weaker effects on zero-sum beliefs.