"Two-pizza teams" is the concept of keeping the team small enough that it can be fed with two pizzas. Small enough for the contribution of each member to make a noticeable contribution, in order to function it needs mutual dependence, a common objective and a single criterion of success for them all.

“双比萨团队”，就是说让团队保持在两个比萨能让队员吃饱的小规模。团队要小到让每个成员都能做出显著的贡献，并且相互依赖，有共同目标，以及统一的成功标准。

If you're working in a group bigger than 15 people, you're fighting human nature. The number of the group members varies from three to twelve or fifteen, and perhaps optimizes somewhere around ten.

如果你在一个大于15人的团队里工作，你就是在和人类本性对抗。团队成员数量可以是3到12或者15个，最佳的成员数量是10个。