Don’t worry if you think writing reviews of your employees is one of the toughest duties you have to do as business manager. That feeling is perfectly normal. Anyone who has a fair bone in his or her body(or even just the fraction of a conscience) knows it’s not just easy to lay bare another person’s flaws to come up with the appropriate performance review phrases. What’s worse is that as an evaluator you might be the possible cause for someone’s dismissal from the company.

If you are a business manager assigned to this most unenviable of tasks, how do you know you are giving them a fair assessment? Actually, there are some things that can impair your judgment about how some employees are doing.

1. Employee Tenure

The most common bias is tenure of the employee being evaluated. Business managers might choose to go too easy on a newbie who has been there for a month and too hard on someone who has been there for years. While it is understandable that those “veterans” in the business should already know the ropes by now. Be sure you aren’t letting the new ones off the hook just because you think they don’t know any better.

2. Only Recent Activity

Another thing you might be unknowingly basing your performance appraisal phrases on is the recent actions of any employee. Chances are that if he or she just did something recently that was so brilliant or screwed up so badly, this might color your review. As much as it sounds cliché, it is always best to base your assessment taking into account his or her overall performance since the last evaluation.

3. Your Managers

You might not know it, but you might also become influenced by others. Especially by your superiors when they heap praise or blame on workers. This praise or blame can be formally stated during a board meeting, or briefly come up during a snack break or just casually mentioned when you met at the water dispenser. You naturally look up to your bosses and in some cases you might translate their words into law. This is more so when you someone compares the performance of an employee to how others work. You might not know it but inside you might have already formed an opinion of that employee.

4. Strengths and Weaknesses

It might be funny, but the actual strengths and weaknesses of an employee might also warp your evaluation. You might be too focused on one forte of one person that you forget he has requires some major improvement in another field. It could also be vice-versa; you are too focused on the shortcomings of a worker in an aspect of his or her job you forget they shine in another. How do you counter this bias? By taking the employee’s entire skillset into consideration, not just that one strength or weakness.

5. Association with Team Successes

The last but certainly not the least of these biases has to do with association. You figure several employees work as a team. Whether they succeed or fail in a task should be credited to or blamed on their teamwork. So that means that they deserve to have a “blanket” or cookie-cutter evaluation right? Wrong. Sadly managers turn to this “strategy” when they are too lazy to conduct and individual assessment or realize the deadline for the evaluations is fast approaching and they still have much to do.

It’s never easy to put others into the hot seat, but since this is part of your job as a business manager the least you can do is to make your performance review comments a fair assessment of those you have working under you. Your company will only be the better for it.