One Bad Apple
What's quietly poisoning your team
We’ve all heard the expression “one bad apple spoils the barrel.”
At some point or another, we’ve all had that person on our team, too. They’re capital-T toxic. They may be actively undermining their colleagues. Gaslighting them—and you.
It can take a while to see it—they’re often good at making you think it’s you, not them—but once you do, you can’t unsee it.
It’s pure poison that will destroy your team if you don’t address it quickly.
One bad apple, indeed.
More insidious apples
There are other types of bad apples—ones less obvious, and in some ways more insidious—because they mean well.
Mediocrity (your underperformers) and martyrs.
They’re not bad people, which makes it all the more difficult to see how they’re silently eating away at your team, rotting it from the inside out.
Mediocrity slowly drains the life out of everything.
Your best people notice what you tolerate. Before long they disengage. Or simply leave.
They don’t want to carry the weight of someone who isn’t pulling theirs. They want teammates who will push them to be better—ones who can help them succeed.
Weaponizing the mission
And then there’s the martyr. Like mediocrity, they don’t look like a problem at first. They’re passionate. Principled. Convicted.
They position themselves as the arbiter of what’s “right” for the company. Everything is framed as protecting the mission. Over time, that becomes a weapon used to shut down ideas, challenge decisions, and undermine others.
The martyr doesn’t build alignment. They quietly create division instead. If you’re not meeting their personal litmus test, you’re not just wrong—you’re a problem.
Mediocrity lowers the bar. The martyr sets a bar only they can meet.
None of these people—not even the toxic ones—wake up with the intent to hurt your team. But intentions don’t matter. Actions do.
All of them will break your culture and your team—if you let them.
Bonus read: Niceness can be an equally insidious culture killer.
