You notice something odd happening in your team meetings.
Your usually engaged designer has stopped volunteering ideas. Your most enthusiastic developer, the one who always asks “can I try that?”, has gone quiet. The energy in your standup has shifted from collaborative to… procedural. People are just “going through the motions.”
Then, three weeks later, your top performer hands in their notice. In the exit conversation, they’re diplomatic. They talk about “new opportunities” and “career growth.” But when you push a bit, they finally say what’s really going on: “I just couldn’t deal with [person’s] attitude anymore. It was exhausting coming to work.”
And suddenly, the last six months click into place. All those small moments you dismissed as “not that bad” were actually a pattern. While you were focused on deliverables and deadlines, one person’s energy was quietly poisoning your team culture. Their work was actually fine. Their impact was toxic and directly affected those around them.
Here’s what I’ve learned after making this mistake more than once. By the time you notice the impact, you’ve usually waited too long. Some of your best people may already be considering their options.
Today, I want to talk about the team member whose performance is acceptable but whose presence is damaging your culture, why this is harder to spot (and act on) than traditional underperformance and what you actually need to do before it costs you the people you can’t afford to lose.
The problem that you can’t see in your performance metrics
Performance issues are relatively straightforward to identify and address. It’s the standard stuff such as:
- Someone misses a few deadlines.
- Their work quality drops below that they’re capable of.
- They’re not hitting their targets.
You have metrics, examples and clear standards to reference. The same can even be said of attitude problems which may not be quite as clear as performance metrics, but are still fairly easy to draw examples from.
On the flip side, energy issues are different. They don’t show up in your project tracking software. They don’t appear in your delivery reports. They’re not captured in your OKRs.
But they spread faster than any performance problem ever could.
Why?
Performance issues (mostly) are contained to one person. Yes, a drop in performance can affect other team members, but it’s clear where the problem is coming from and who it’s affecting the most. If someone’s work is substandard, that’s their problem to fix (with your support).
Energy issues are viral. One person’s constant negativity doesn’t stay with them. It seeps into every interaction, every meeting, every Slack thread they’re part of.
And your good people, the ones you most want to keep? They often tolerate a lot before they speak up. They’ll try to work around the negative person. They’ll compensate for the resistance. They’ll keep their heads down and hope it gets better – particularly if their actual performance is generally not an issue.
What most of them won’t do is tell you how much it’s affecting them.
Let’s get a bit more specific about what this actually looks like, because “negativity” feels too vague.
Examples of negative energy problems
I’m talking about the team member who responds to every new initiative with “We already tried something like that” or “That won’t work here.” I’m talking about the visible sigh when you announce a change. The arms crossed in meetings. The eye rolls when someone else suggests an idea. The person who’s clearly doing emails during your team discussion to signal their disengagement.
I’m talking about the Slack responses that always find the problem, never the possibility. When you share a new direction, they’re the first to respond with scepticism. When someone proposes a solution, they immediately point out why it’s flawed. When the team is trying to build momentum, they’re the drag factor.
Their own work output might be fine. They might hit their deadlines. Their client deliverables might be acceptable.
But here’s the cost you’re not measuring: Your most innovative team member stops suggesting ideas because “there’s no point.” Your keen new joiner learns that enthusiasm isn’t rewarded here. Your senior people start looking for environments where they can actually build something without constant resistance.
They can also kill momentum which is so important to so many teams and companies.
What momentum killing actually looks like
The tricky thing about momentum killers is that their behaviour often feels defensible in isolation. Any single instance seems too small to address. It’s the pattern that’s the problem, but patterns are harder to see when you’re in them.
So let’s talk about what this actually looks like in practice, because if you can’t name it or call out examples of it, you’re going to find it very hard to address it.
Meetings and calls
Try to watch for the person whose reactions shut down discussion before it really starts.
You introduce a new project or direction. Before anyone else can respond, they sigh audibly. Or they lean back and cross their arms. Or they say “OK” in a tone that clearly means “this is stupid.” Or they immediately respond with “How is this different from [previous thing] that didn’t work?”
The conversation doesn’t build. It stalls. Other people, the ones who might have had ideas or questions, stay quiet. They’ve learned that enthusiasm will be met with cynicism, so why bother?
I’ve sat in meetings where one person’s physical reaction (literally turning away from the screen in a video call, or very obviously doing something else) sent a clear message to everyone else: this isn’t worth our attention. And the meeting never recovered.
Internal asynchronous communication (Teams, Slack etc)
In this type of communication, momentum killing shows up differently but just as effectively.
You announce something in Teams or Slack. The momentum killer is often the first to respond and their response sets the tone for everyone else. They immediately point out problems. They reference past failures. They ask questions designed to highlight flaws rather than to understand or improve.
Or they create side threads that undermine the main conversation. You’re trying to build alignment in the main channel. They’re in DMs with others, spreading doubt.
Here’s a specific example: I once announced a new client project in our team channel. The work was a good opportunity, slightly outside our usual scope but definitely within our capabilities. Within five minutes, one team member responded: “Wasn’t this a really difficult project last time we did it? What’s different this time?”
Two other team members had typed responses (I could see the “…” indicator) but then didn’t send them. Later, I found out they’d both had ideas but decided there was “no point sharing them if everyone’s already negative about it.”
One comment. Five minutes. Multiple ideas never shared.
The justification trap
This is where most managers (including me, multiple times) get stuck.
We tell ourselves things like:
- “They’re just being realistic.”
- “They have a right to their opinion.”
- “I don’t want to police people’s attitudes.”
- “They raise valid concerns.”
All of these things might be true. And they’re also irrelevant if the impact is toxic and shuts down other people.
Here’s the distinction that matters. Healthy scepticism proposes alternatives. Momentum killing just stops forward movement.
Healthy scepticism sounds like: “I’m concerned about [specific thing] based on [specific experience]. What if we approached it by [alternative suggestion]?”
Momentum killing sounds like: “That won’t work” followed by nothing constructive.
Healthy scepticism asks questions to understand and improve: “How are we planning to handle [challenge]?”
Momentum killing asks questions to highlight impossibility: “Have we thought about [a long list of everything that could go wrong]?”
The difference isn’t about whether concerns are valid. It’s about whether the person is trying to make things better or just trying to stop things happening.
This is particularly true if you work in an environment where creativity is paramount. Having someone who is always looking for problems in ideas is never going to be positive for the team as a whole.
The conversation you should have had three months ago
Right, let’s talk about what you actually do. Because awareness without action just means you’ll watch the problem unfold in slow motion.
Step one: Name the specific behaviour, not the attitude
Avoid saying things like: “You’re being negative” or “Your attitude is affecting the team.”
Instead, try to give specific examples that are as recent as possible: “In the last three meetings, when [specific initiative] was discussed, you responded with [specific words]. Here’s the impact that had: [specific outcome].”
Sidenote: this is actually quite similar to the approach I recommend in the SBIA feedback framework.
For example: “In Monday’s standup, when I introduced the new client project, you said ‘Here we go again’ and visibly sighed. Then you said ‘Didn’t we already try something like this?’ In that same meeting, [team member] started to share an idea but stopped mid-sentence. After the meeting, they told me there was ‘no point’ sharing ideas when the tone is already negative. This is the third meeting this month where I’ve seen this pattern.”
The more specific you are, the harder it is for them to dismiss or deny. You’re not attacking their character. You’re describing behaviour and impact.
Step two: Distinguish between dissent and drag
Make this distinction clear: “Disagreement is welcome here. Scepticism that leads to better solutions is valuable. What’s not acceptable is creating an environment where other people feel like they can’t put forward ideas or speak up.”
Explain what constructive challenge looks like versus what derailing looks like:
Constructive: “I have concerns about [thing] because of [reason]. What if we approached it differently by [suggestion]?”
Derailing: “That won’t work” with no alternative offered. Or “We tried that before” with no acknowledgement that circumstances might be different.
You’re not asking them to be artificially positive. You’re asking them to be constructive rather than destructive.
Step three: The non-negotiable standard
This is where you need to be unambiguous: “It’s fine to have concerns. It’s not fine to create an environment where others stop contributing. That’s the standard. It’s not negotiable.”
Some managers worry this sounds too harsh. I’d argue the opposite. Clarity is kind. Your job is to protect the team environment and culture. This means being clear about what’s acceptable and what isn’t.
Step four: Follow up actions
Like any good feedback, don’t leave this conversation in the abstract. Be specific about what needs to change:
“In team meetings, I need you to either contribute constructively or hold your concerns for a one-on-one with me afterwards. Specifically, that means if you have objections, I need you to either propose an alternative or ask genuine questions to understand the approach better.”
“In Slack, when new initiatives are announced, I need you to take 10 minutes before responding. If you have concerns, bring them to me directly rather than posting immediately in the channel.”
Set a timeline: “I want to see this change over the next month. We’ll check in weekly.”
Be clear about consequences: “If this doesn’t change, we’ll need to have a different conversation about whether this role is right for you.”
I know that this type of situation is uncomfortable. I’ve put off these conversations myself, telling myself it wasn’t “bad enough yet” or that maybe it would improve on its own.
But the truth is that it doesn’t improve on its own. And every week you wait is another week your best people are deciding whether to stay.
Your top performers are watching what you tolerate. They’re watching whether you’ll protect the team environment or whether you’ll prioritise avoiding a difficult conversation. Show them you won’t tolerate momentum killing, even when the work itself is fine.
Because here’s the thing: You’re not just managing individual performance. You’re managing the environment in which everyone performs. And if that environment is being damaged by one person’s energy, your job is to fix it before it costs you everyone else.
