How to Spot a Toxic Coworker

Every company has a wide range of employees: the good, the bad, the average and the toxic. While bad employees — the perpetual Internet surfers or two hour lunchers — don't help with getting things done, it's actually the toxic coworker that is the most dangerous and costly of all, affecting both workplace morale and the company's finances in ways that often go overlooked.

To identify a toxic coworker, you have to understand the difference between toxicity and poor quality. While you can have employees that perform at below-average levels and cost companies in terms of lost productivity, the toxic coworker tends to perform better than most on the job but is still a greater liability in terms of their overall influence.

A 2015 study from Harvard Business School looked at employment data from more than 50,000 workers in 11 different companies and determined that avoiding toxic employees was more important (i.e. cost-effective) than hiring "superstars" who outperform in their duties. That's because toxic coworkers aren't just hazardous to a company's bottom line, costing the firm billions of dollars, they're also infectious — creating conflict and dissatisfaction in the workplace.

What defines a toxic coworker?

Toxic coworkers are characteristically "self-regarding," the researchers found. They care more about their own success than helping peers and are also generally overconfident in their own abilities. Toxic coworkers also appear to emphasize the importance of following rules without exception — though they cut corners and break rules nonetheless. That's a recipe for disaster, leaving companies vulnerable to the spread of toxicity.

"That is kind of counterintuitive," economist Dylan Minor, who co-authored the study, told the Harvard Gazette. "In a simple world, we would just ask someone, ‘Do you always follow the rules?’ And if you do, then of course, you’re not going to ever break them. But I find very strong evidence in my study that those that say ‘Oh no, you should always follow the rules’ — versus those that say ‘Sometimes you have to break the rules to do a good job’ — that the people who say ‘I never break the rules’ are much more likely to be terminated for breaking the rules."

Screening for Toxic Employees

While employers often focus on hiring and retaining the best employees — who the researchers describe as "superstars" — the study gives reason to believe that avoiding toxic workers will save companies the most in the long run. As far as cost-savings is concerned, hiring a superstar has an average return of about $5,300 while avoiding toxic workers has a return of more than $12,400. The study suggests screening employees for overconfidence, self-regarding behaviors and claims that rules should always be followed. Since productivity is also hallmark of toxic workers, researchers caution hiring managers against using performance as the only criteria of success, and focusing on corporate citizenship as well. “Most managers, if you ask them, ‘Do you want to have someone who cares more about others?’ They’d say, ‘Of course, I want that.’ But at the end of the day, most of them aren’t hiring much based on that," Minor said.

Avoiding toxic workers is the best practice, of course, but there's also room for reform, the study found. It's just that the time and resources it takes to reform toxic employees is often not worth the added expenses for most companies. So the takeaway is to keep your eyes open for the signs of toxicity and maybe don't spend as much time focused on the superstars.

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