Why self-assured leaders win, and why being grounded matters just as much for your well-being as for your success.

In the 1990s, Harvard professor Amy Edmondson made a surprising discovery.

She was studying medical teams and expected the best ones to report fewer mistakes. Instead, high-performing teams reported more.

Not because they were careless. But because their leaders created an environment where people felt safe to admit errors. When a nurse could flag a potential medication issue without fear of being dismissed, or a resident could question a senior doctor without career risk - that’s when teams actually performed better.

Edmondson called this psychological safety: a climate where people can speak up, ask questions, and take risks without fear of punishment. Research since then confirms it’s one of the strongest predictors of team performance, creativity, and innovation.

Google's Project Aristole later confirmed this at scale. They studied 180+ teams across 250+ variables and identified five drivers of success: psychological safety, dependability, structure & clarity, meaning, and impact. Interestingly, without psychological safety, the other four weren’t enough. Teams stagnated.

And what allows the leader to contribute to psychological safety? Their self-assurance.

Ego-driven leaders shrink teams. They default to blame and defensiveness. People learn to protect the leader’s image instead of solving problems.

Self-assured leaders expand teams, giving space to muliply others' brilliance.

Setting aside the leader's own capability, their character strongly predicts how well they leverage others' strengths.

So here’s a quick self-check:

- Do you balance critique with recognition?

- Do you ask questions as often as you advocate?

- Do you create conditions for resilience and creativity?

If you don't, is it because of some insecurity?

It's no coincidence that Harvard Business School's leadership curriculum starts with self-management before managing others. When leaders learn to question themselves as rigorously as they question their team's analysis, everyone wins.