Culture is not values on a wall. It is what gets rewarded, tolerated and promoted — and it changes fastest exactly when you are too busy to notice.
Culture is the set of behaviours a company actually rewards and tolerates.
At ten people it is transmitted by proximity — everyone sees how the founders behave. Past about thirty, most people never work directly with a founder, and culture has to be transmitted by something other than being in the room.
Because it degrades silently. Nobody announces that standards slipped; it happens through a series of individually reasonable decisions, usually made under time pressure.
The strongest signal is not what you say. It is who gets promoted and what you tolerate from someone who delivers results.
A company says it values careful, honest work. Its highest-performing salesperson repeatedly over-promises on the roadmap to close deals, and support absorbs the fallout.
Nothing is said, because the numbers are good. Within two quarters two other reps have started doing the same. The stated value was never the culture; what was tolerated was.
Writing values that no decision would ever contradict. "Integrity" and "excellence" cost nothing. A real value is one you can point to a decision where it cost you money.
"We write things down before we discuss them" is testable. "Excellence" is not.
Promotions are the loudest cultural statement a company makes. Everyone reads them correctly.
This is the whole test. Tolerating it once tells everyone the value is optional.
Culture transmitted only by proximity stops transmitting the moment new people stop sitting near you.
As the company grows, what you write is what scales. What you say in a room reaches the room.
From the first hire, and with real deliberateness past about twenty people, when most new joiners no longer work directly with a founder.
Never — but avoid the formal exercise of writing values while you are still two people. At that size the culture is simply how the two of you behave.
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