I Was a Terrible Boss.

Here’s What It Cost Me.

When we started NanoTemper, we were just a handful of people.

Tight rooms. No windows. Long days. No idea what we were doing, except building something we believed in. From our first 10 employees, only one is still with us: Gernot.

He started as an intern. Built our first instruments by hand. Today, he’s our Global Head of Production.

He stayed. The others left.

Not because the startup life was too hard. Not because of the pressure. They left because of me.

My Biggest Leadership Failure

Let me be brutally honest.

I failed people. People who had talent. People who showed up. People who believed in us.

Like Hüseyin.

He was one of the best electronics engineers I’ve ever worked with.

And I made his life miserable: I shouted at him. Belittled his work. Didn’t trust him.

Why?

Because deep down, I knew he was better than me.

Instead of learning from him, I let my insecurity run the show.

He left after a year.

Then there was Iman.

A foreign student, interning with us.

I dismissed her in my mind before she even started.

Assumed she wouldn’t contribute much.

Today, she’s a founder of an AI company.

And making headlines.

I couldn’t have been more wrong.

Svenja. Sabine. Chris. Max.

One by one, they left.

Because when you work long hours, under pressure, in a team without daylight, and your boss is an ungrateful, insecure idiot, you leave.

Why I Failed as a Leader

I went from PhD student to CEO overnight.

No experience. No mentors. No clue how to lead.

And so I made my team pay the price for that learning curve.

That’s what still stings the most.

What I Learned (Too Late)

Here’s what I know now:

– Talented people need trust, not control.

– People don’t leave jobs. They leave bad bosses.

– Your own insecurity can destroy your most valuable people.

I learned it all the hard way.

And at the expense of people who gave us their time, their energy, and their trust.

Some I’ve apologized to.

Others, I’ve lost touch with.

But their names stay with me.

And they made me a better leader—eventually.