Kickresume’s 2024 survey has found that 85% of people have dealt with an annoying coworker, which means that almost everyone has had the displeasure of coming across the workplace vampire that drains energy and patience by being an inconvenience. What I would like to know, though, is how the lucky 15% were never faced with a frustrating colleague. Please, e-mail me your secret! Just kidding… Or am I?

58% of those who have worked with despairing coworkers said that their behavior affects their productivity, and only 13% can stay focused on their tasks despite what’s happening in their environment.

The survey also found the top five types that make employees' blood boil the most:

1. Credit stealer (33%)
2. Micromanager (32%)
3. Chronic complainer (30%)
4. Personal space intruder (30%)
5. Lunch thief (27%)

"Toxic behavior is not always loud or obvious. More often, it shows up in subtle, persistent ways. Dismissiveness, passive-aggressive remarks, gossip, taking credit for someone else’s work, and creating unnecessary conflict all break down trust," says Connie Kurczewski, aesthetic practice consultant and strategic business advisor at Elevated Practice.

"One pattern I see often is what some refer to as “learned helplessness” or “intentional incompetence.” It happens when someone constantly avoids responsibility and expects others to compensate. It might not seem disruptive at first, but over time, it quietly drains momentum and morale from the team."

Other unacceptable behaviors that experts observe in the workplace include bullying, leaving people out of important updates, and spreading rumors.

"An example of toxic behavior in the workplace is if one colleague intentionally sabotages another through dishonesty or speaking disparagingly about them, attacking their character behind their back with the intention of damaging their reputation," adds leadership coach Robina Bhasin at RMB Leadership & Talent Strategy Consulting.

"Another example is an employee who is permitted to be abusive toward others simply because of the power, prestige, or position they hold. Senior leaders are aware of the toxic behavior but simply look the other way, unwilling to address it with the person because they fear upsetting them," she says.

"These kinds of actions can bring down the mood at work. They make people less productive, increase how often employees leave, and can even damage the company’s reputation. Plus, dealing with this kind of negativity day in and day out can take a toll on everyone’s mental health," explains corporate culture and employee relations expert Josh Hart.

"When this kind of behavior goes unchecked, it impacts the whole team," agrees Kurczewski. "Communication breaks down, resentment builds, and even your best people start to pull back. This often leads to lower morale, high turnover, and a noticeable drop in performance. In service-centered businesses, the first signs usually appear in the client experience. I have seen how one person’s unaddressed behavior quietly shifted an entire team dynamic. These situations rarely fix themselves."

"Furthermore, when employees do not feel psychologically safe in the workplace, they are less likely to notify colleagues and senior leadership about mistakes that have been made and less willing to ask questions or share their ideas if they diverge from those of senior leaders," says Bhasin. "This can have devastating consequences for the company's product/service and significantly stifle innovation and growth potential over time."

The workplace culture experts also explained why workers might display unacceptable behaviors towards colleagues. "In most cases, it comes down to one of two things. Either the person lacks the self-awareness or emotional maturity to recognize how their behavior affects others, or leadership has not set clear expectations or followed through when needed," Kurczewski suggests.

"Stress and insecurity can absolutely play a role, but they do not excuse behavior that undermines the team. When the culture of an organization is unclear or inconsistent, people will push boundaries. And when there is no accountability, those boundaries eventually disappear."

Of course, addressing such colleagues' toxic behaviors can be tricky, but it's crucial to talk about it with the person who is causing the trouble directly, says Hart. "It's important to be clear about what’s bothering you and how it affects your work. Setting clear boundaries and getting support from HR or a mentor can also help. And keep track of any incidents, just in case you need to show a pattern of behavior to someone higher up," he says.

"You want to start by observing patterns and writing things down," seconds Kurczewski. "It is easier to have a productive conversation when you can point to specific examples. If you are a peer, speak up respectfully and directly. Be clear about what is not working. If you are a leader, do not wait. The longer you let it go, the more damage it causes. One of the most common mistakes I see is avoiding difficult conversations. But those conversations are what protect the culture, the team, and ultimately the business."

Meanwhile, Bhasin advises trying to understand where the person is coming from, except in situations where an employee has been abusive toward other employees.

"With this insight, I help them deepen their self-awareness and see the impact of their actions on others. With this greater self-awareness, the employee often chooses a path of self-improvement to build more positive relationships with colleagues. And if they are not willing to make changes, there is a separate conversation about their future in the company that needs to happen."

Lastly, Hart notes, "Creating a workplace where everyone feels respected and valued can prevent a lot of these issues from starting in the first place. Encouraging everyone to give regular feedback, training employees on how to communicate effectively, and recognizing when people treat each other well can make a big difference in building a positive work environment."