During my last holiday I had the time to catch up on some reading that had been sitting on my list for a while.
Topics around decision making, cognitive biases and how we form opinions.
One concept that was interesting: The Dunning–Kruger effect.
At the time it felt like an interesting theory about how people sometimes misjudge their own competence.
Two weeks ago, I recognised it in my personal surroundings. A discussion started about a specialised topic. Someone present had real professional expertise in the matter. The kind of expertise that comes from years of working in this particular field.
The conversation shifted and ‘certainty’ entered the room. Something struck me. The person with the deepest expertise spoke with nuance and caution, while the other one spoke with increasing certainty. Experience was careful and confidence was loud. And suddenly that concept I had been reading about months earlier came back to mind. Not as theory,… but in reality.
When expertise stops speaking.
The Dunning–Kruger effect is often used to explain why people with little knowledge can feel very certain about their opinions. But what interests me more is the other side of that dynamic.
Experts tend to be more cautious because they are more aware of the complexity of the topic.
And this tends to lose the room. In many discussions whether in society, organisations or families, the most confident voice often wins, not the most informed one.
And over time something else starts to happen… The people who actually understand the topic sometimes stop engaging altogether. And not because they lack arguments.
The leadership mirror.
That moment also triggered a more uncomfortable reflection for me.
Throughout my career I’ve been (most of the time) fortunate to work with leaders and colleagues who never relied on hierarchy to win arguments.
People who took the time to listen. People who encouraged debate. I realise how valuable such environment is.
Because the real danger in organisations is not that someone overestimates their knowledge.
The real danger is when the people who know more stop speaking up. That’s when mistakes go unchallenged. That’s when confidence starts replacing competence.
Which leads to a question I sometimes ask myself in my role as a leader.
Do the people around me feel comfortable challenging ideas, including mine?
Does hierarchy silently shape the conversation?
It’s easy to say we value open discussion. It’s much harder to build an environment where people genuinely feel safe enough to disagree. Maybe this is one of the hardest leadership challenges.
The Dunning–Kruger effect isn’t just a psychological curiosity. It’s a reminder of something leaders should never forget: Confidence and competence are not the same thing. And good leadership isn’t about always having the right answers.
It’s about creating an environment where the best understanding can surface, even when it contradicts the person with the most authority.
Because when expertise stops speaking up, the problem isn’t psychology anymore.
It’s leadership.