Two-pizza teams are so named because they’re small: 6 to 10 people; you can feed them with two pizzas. The most important aspect of a 2PT isn’t its size, though, but its fitness function. A fitness function is a single key business metric that the senior executive team (the “S-team”) agrees on with the team lead. (North Star Metric)
Once approved, the team is then free to execute relatively autonomously to maximize its fitness function
there’s no need to coordinate even across teams, let alone across divisions, to get something done
Epilogue: This post describes Amazon as I knew it when I worked there 2004–2007. People who were there more recently tell me that since then, fitness functions themselves have been abandoned, although the ideas of accountability, autonomy and ownership are still core and very strong.