So Amazon supposedly has a “two pizza rule” to limit the size of meetings – the convention is that two pizzas should be sufficient to feed all participants in any meeting. While pizza is not necessarily served at most meetings, the rule effectively implies that a meeting can’t have more than seven or eight people.
The point of the rule is not hard to see – a meeting that has too many people will inevitably have people who are not contributing, and it’s a waste of their time. Limiting meeting size also means cutting total time employees spend in meetings, meaning they can get more shit done.
While this is indeed a noble “rule” in a corporate setting, it just doesn’t work for parties. In fact, after having analysed lots of parties I’ve either hosted or attended over the years, and after an especially disastrous party not so long ago (I’ve waited a random amount of time since that party before writing this so as to not offend the hosts), I hereby propose the “anti two pizza rule” for parties.
While five to eight people is a good number for a meeting, having enough people contributing but no deadweight, the range doesn’t do well at all for more social gatherings. The problem is that with this number, it is not clear if the gathering should remain in one group, or split into multiple groups.
When you have a “one pizza party” (5-6 people or less), you have one tight group (no pun intended) and assuming that people will get along with each other, you’re likely to have a good time.
When you have a “three pizza party” (more than 10 people), it’s intuitive for the gathering to breakup into multiple groups, and if things go well, these groups will be fluid and everyone will have a good time. Such a gathering also allows people to test waters with multiple co-attendees and then settle on the mini-group that they’ll end up spending most time with.
A two-pizza party (6-10 people), on the other hand, falls between the two stools. One group means there will be people left out of the conversation without respite. In such a small gathering, it is also not easy to break out of the main group and start your own group (again, seating arrangement matters). And so while some attendees (the “core group”) might end up having fun, the party doesn’t really work for most participating parties.
So, the next time you’re hosting a party, do yourself and your guests a favour and ensure that you don’t end up with between 6 and 10 people at the party. Either less or more is fine!
You might want to read this other post I’ve written on coordinating guest lists for birthday parties.