Tribal knowledge is a liability
The things 'everyone just knows' are exactly the things that break when someone leaves. Undocumented knowledge is borrowed time.
Every team accumulates tribal knowledge — the unwritten understanding of how things really work, the quirks, the 'oh, you have to do it this way' that nobody recorded. It feels like culture and competence. It's also a liability that comes due the moment the right person isn't around.
Unwritten means unreliable
Knowledge that lives only in people's heads is invisible until it's missing. New hires take forever to absorb it. It contradicts itself between people. And when someone leaves, a chunk of it walks out the door with no backup. You can't manage what you can't see.
Externalize it
The goal isn't to bureaucratize everything — it's to move the load-bearing knowledge out of heads and into docs, processes, and systems where it's durable and shared. The best version encodes the knowledge into tools so the right way is the default, not a thing you have to know.
Tribal knowledge feels like expertise. It's actually a debt that comes due the day the expert leaves.