By “high growth”, I mean in terms of employee count and roughly doubling or more every year. Even at slower growth rates, some of the phenomena I’ll describe may be relevant.

Two reasons why building teams in high growth is difficult: can’t assume stable teams, can’t rely on cultural osmosis.

In high growth, the odds are the teams won’t be stable

There are several options to accommodate new people:

Sink or Swim; Split and Absorb; Absorb and Split

1. Sink or Swim. Keep the older teams as-is and add the new people to brand new teams. This keeps teams stable and likely ensures that all new teams will struggle;
2. Split and Absorb. Split up the older teams (aka not stable) and absorb new people in the new teams. This means there’s a mix of veterans and newbies;
3. Absorb and Split. Add new people to existing teams. This will eventually lead to the teams becoming too large (aka not stable) and splitting (also not stable).