All Things Workplace has a nice brief summary of the Halo Effect and the Horn Effect, which can both come into play in workplaces, and in performance reviews. Be sure that you’re not falling into either trap.
The Halo Effect is when a person with an outstanding characteristic colors one’s total judgement of that individual. In other words, they are suddenly seen as having many outstanding traits, that they do not, in fact, have.
The Horn, or Devil, Effect is just the opposite: a person deficient in one characteristic is seen as being deficient in many other areas that they are not.
As if that weren’t bad enough, here’s what I see as the very wort part of such judgements: they are a self-fulfilling prophecy. “We live up to our expectations. People who expect to be successful are more likely to succeed. People who expect failure are more likely to fail.”
Be sure that you are fairly judging employees on all of their capabilities or deficiencies. And be sure you are telling them what they are doing well, what you want to see more of, and where you want to see improvement.
For further reading:
- The Halo Effect in Business
- The Halo Effect: When Your Own Mind is a Mystery
- Mental Model: Horns Effect and Halo Effect
- Halo/Horn Effect