You can teach Kubernetes. You can't teach someone to stop being a jerk.
Tech leads are made, mostly. The asterisk is the short list you cannot install in an adult: honesty, empathy, the credit reflex, decency under pressure. The two-pile sort, the promotion I refused at a real cost, and the legibility trap that hands brilliant jerks the title.
You can teach almost anyone Kubernetes. You cannot teach someone to stop being a jerk.
I once had a quiet engineer whose raw technical output would have landed her mid-team. But she had the entire non-negotiable pile. People trusted her. She gave credit without being prompted. When she was wrong she said so in a flat voice and moved on, so nobody ever had to manage her ego.
I made her a tech lead. I spent a year topping up the teachable pile. She became one of the best leads I've ever had. Everything she was missing was teachable.
Then there was the obvious pick. Genuinely the strongest engineer in the room. Everyone assumed the role was his. He half-expected it himself. And every signal in the non-negotiable pile was red. He took credit by default. He treated being corrected as an attack to be repelled. He was charming to people who could help him and dismissive of people who couldn't.
I didn't promote him. That call cost me a hard month of defending it. On the visible tally, the one made of commits and design docs, he was the obvious choice. Everyone knew it. And every argument I had was the kind that doesn't fit a spreadsheet.
"Are leaders born or made" is the kind of question that sounds profound and mostly ruins dinners. For tech leads it has a working answer.
Made. Mostly. With one asterisk that matters more than the rule.
What you can build
Most of the job is trainable. The list is longer than people think:
- Technical range across the team's stack.
- A feel for where the system will bite next.
- Thinking two quarters ahead instead of one ticket ahead.
- The mechanics of running a project while three things go wrong at once.
All of it grows with reps and a decent mentor. None of it is a verdict. A candidate short on these gets a development plan. I've watched people weak on every single one of them grow into excellent leads inside a year.
How I actually run that year is its own post. This one is about who gets the year at all.
The asterisk
Almost everything the role needs, you can build. The one part you cannot build is character. And character decides who gets the title.
The asterisk is the short list of things you cannot install in an adult:
- Communication that survives stress.
- Empathy.
- Plain honesty.
- The reflex to give credit instead of pocketing it.
- Ordinary decency when decency is inconvenient.
These are mostly present by the time someone is grown, or they mostly aren't. No two-day workshop has ever closed that gap.
I've watched people try to coach an adult into caring about other people. It doesn't take. What you get is compliance. The performance of warmth in the meeting. The right vocabulary, the active-listening nod. And the team smells the difference within a sprint. They sit next to this person forty hours a week.
The mechanism is simple. Coaching changes what people say. It doesn't change what they want. Performance takes effort, and load takes the effort away. What's left under load is the person.
The two piles
This hands you a clean sort. Two piles.
The non-negotiable pile:
- Communicates clearly.
- Reads a room.
- Behaves well when nobody senior is watching.
- Makes a call and owns it when it goes wrong.
- Hands work out instead of hoarding it.
The teachable pile:
- Depth in your stack.
- Long-range vision.
- Adaptability.
- The actual craft of mentoring.
Screen hard on the first pile. Be generous on the second. Most selection processes do the exact opposite. Four hours measuring the teachable pile to two decimal places. One coffee chat guessing at the rest.
The legibility trap
That month has a name now. I call it the legibility trap.
Skill is legible. You see it in code review, in system design, in how someone takes apart a hard bug. It leaves artifacts: commits, docs, the visible tally. It survives a promotion packet.
Character is not. It only shows under load. How someone treats a struggling junior when they themselves are slammed. Whether they tell you the bad news early or let you find it in production. That evidence arrives as anecdote, and anecdote reads as bias in a calibration meeting. So it gets discounted.
The result is systematic. Organizations over-weight what they can see, and the predictable output is the brilliant jerk handed a leadership title because the spreadsheet said he earned it. It's the single most expensive promotion mistake I know. Expensive precisely because it looks correct, right up until the team starts quietly leaving.
The floor
Clearing the non-negotiable pile doesn't make someone a great lead. It makes them safe to develop into one. The quiet engineer still needed the year.
And the brilliant-but-impossible candidate is very good at making you forget the floor exists. Every conversation about him drifts to the teachable pile, because that's where he is spectacular. But the teachable pile was never the question.
Screen hard on character. Be generous on skill. Promote a jerk anyway and he doesn't grow into the role. He gets a bigger blast radius. And a team that starts keeping its CVs current.
I spent a hard month defending one decision and a year developing the other.