Series B is where culture dies — and the 4 systems that prevent it.

Culture in a 30-person company is transmitted by proximity. The founders are in the room; values are caught, not taught. Somewhere between 80 and 200 employees — the typical Series B band — that transmission mechanism breaks. New hires no longer meet the founder in week one. The values document on the wall starts to read like marketing copy. Decisions that used to take 20 minutes in person now take three meetings and a Notion doc. Across the 14 Series B companies I worked with in 2024–25, the ones that kept their culture had installed four specific systems before the breakage. The ones that lost it installed the same systems 18 months later — and spent 24 months trying to recover.

The 4 systems, installed before they're needed

• A written decision-making operating model: who decides, who's consulted, who's informed, on which categories of decisions. Without this, every cross-team decision becomes a meeting.
• A weekly business review with a fixed agenda, owned by the CEO, attended by the top 10. Without this, the company's metrics live in 14 different dashboards and nobody agrees what's working.
• A monthly all-hands with a 60/30/10 structure: 60% metrics and progress, 30% one deep-dive on a hard topic, 10% Q&A. Without this, all-hands degrade into theater within 6 months.
• A 'red team' culture review every quarter — 5 random employees, 90 minutes, what's broken about how we work. Without this, the founders are the last to know.