Ideas · the objection I get most

“Focus on one thing, or none of them will work.”

I hear it whenever someone learns that I have a day job at IBM, twins, a works-council seat, and eight projects in various states of alive. Usually followed by a Musk anecdote, delivered as either praise or warning. Both miss what is actually going on, so here are five pictures of what I have measured on my own bench.

The short version: focus is a rule about capital and headcount. It was never a rule about a person’s evenings. And the price of one lap around a project fell so far that the advice needs re-pricing, not repeating.


01 · the arithmetic changed

The advice was priced in weekends.

“Do one thing properly” assumed a fixed cost per lap: idea, build, show it to someone, learn, repeat. That cost is the whole reason the advice existed — you only got a handful of laps per year, so you had better spend them all in one place.

BEFORE — ONE BUILD LAP 6 weekends NOW — ONE BUILD LAP 1 evening
Both bars are one lap: from an idea to something a stranger can open. The bar did not get better. It got cheaper.

When one lap costs six weekends, spreading yourself over four projects means one lap each per year — which really is useless. When it costs an evening, four projects is four laps a week. The advice didn’t change. The price did.

Where this number comes from

It is the “before ↔ after AI” line in my own lifecycle map: before, one lap cost six weekends of writing every line yourself — this is where most projects died, quietly. Not a study. My bench, both sides of it.

02 · the one that answers the objection

Eight projects. Two of them are expensive.

“Eight projects” sounds like eight times the work. It isn’t, and this is the picture I wish I could hand people instead of arguing. What costs a life is not having projects. It is having them in the expensive stages — the ones that need strangers, money and my calendar, not just my attention.

EXPENSIVE IDEA BUILD LAUNCH SCALE PAUSE EXIT chilld Pentomino Duel Sendely FastBrand the video tool children’s book tool BYTE Challenge STEM GIrls 2 of 8
Every project I have, on the stage it is honestly on today. Two dots fall inside the shaded band. The other six cost curiosity, evenings, or nothing at all.

A paused project costs nothing but the honesty of the label. An exited one costs a mentoring call now and then. Only Launch and Scale are greedy — and I keep at most two in there, not by discipline but because there is no room for a third.

So the real rule isn’t “work on one thing”. It is: hold as many as you like, but never let more than two be expensive at once. That is a load limit, and load limits are easier to keep than vows.

Why Pause and Exit are stages and not failures

The children’s book tool is paused because I published the Bitsy books the hard way once, loved the writing and hated the production details — so it waits for an agent that can carry the annoying parts. BYTE and STEM GIrls are exits: both handed over and still running without me. If those three counted as failures, I would look reckless. Labelled honestly, they are what makes room for the two that are live.

03 · the anecdote everyone brings

Musk is the wrong comparison — different verb.

He gets quoted at me in both directions: as proof it can be done, or as proof that people who try are insufferable. Neither works, because the thing he does is not the thing I do.

WHOSE WEEK HE ALLOCATES …and tens of thousands more WHOSE WEEK I ALLOCATE me, after bedtime
His companies employ tens of thousands. My projects employ one person, part-time, with a hard stop when the twins wake up.

He isn’t doing five things at once. He is deciding what five organisations do — a delegation problem with a private jet attached. I am doing one thing at a time, in the two hours after bedtime, across a portfolio that mostly sits still.

Quoting him at a person with evenings is like quoting a shipping line at someone with a canoe. Same water. Nothing else in common.

04 · what focus looks like from the front

A pause is an option, not a corpse.

Every focused career sounds focused afterwards. Told forwards, it is a pile of things that sat still for years until one of them was suddenly worth finishing.

2014 2026 school paper twelve years asleep — and nobody called it focus live game
My school research paper on pentominoes, 2014. It became pentomino.club in 2026. Twelve years of doing nothing about it — then a few weeks.

If I had “focused”, that paper would have been thrown away in 2015 as a distraction. Keeping a project doesn’t mean working on it. It means not deleting the option.

The part that makes it real, not romantic

The pentomino world championship has run at the Max-Planck-Gymnasium in Saarlouis since 2004 — 80+ players a year, its own rules. I won it; my siblings hold titles too. The paper was the groundwork. What changed in 2026 wasn’t inspiration, it was that a build lap got cheap enough that opening a school-gym championship to everybody became an evening’s work instead of a project.

05 · why the count keeps rising

Not eight projects. One workshop with eight benches.

The objection assumes the projects compete for the same hour. Mostly they don’t — because the ones I build for my own busywork end up serving the others. Each new tool makes the next project cheaper, which is the opposite of spreading thin.

TOOLS I BUILT FOR MY OWN BUSYWORK Sendely posts for all of them FastBrand brands all of them the video tool still an idea WHAT THEY SERVE chilld Pentomino Duel community formats
The tools are not extra projects competing for time. They are the reason the next project takes an evening instead of a season.

This is also the honest answer to “is it a hobby or a business?” Neither, quite. It is the research budget — and it happens to be the only budget I control completely.


the part where the advice is right

When “focus on one thing” is correct

I am not arguing that the advice is nonsense. It is precise advice that gets repeated outside its own conditions. It holds, hard, when:

None of those describe my evenings. All of them describe a funded startup. That is the whole disagreement: the advice is about a company. The objection is aimed at a person.

And one thing I won’t dress up: this only works because Pause and Exit are real stages for me, with real labels, in public. A portfolio without honest labels isn’t a portfolio. It’s a pile.


← Ideas  ·  Carolin Neumann  ·  August 2026