1- Face to face communication is more efficient
- facial expressions, voice inflections, and body language are all part of communication
- it is faster to talk than type and read
- you can pull in other forms by using a wipe board or pointing at a diagram
- there is less mis-communication
You can jump in when you know something that helps. You can listen when you know it helps you. You can ignore it when it doesn't matter. Information becomes transferred by default and this is referred to as osmotic communication.
3- Communication decreases by the length of a school bus
I was sitting in a session with Alistair Cockburn at Agile 2007 when he started to describe this study he did for some big company. Simply put, a person's likelihood of getting up from their desk and walking to talk to someone about something they need decreases exponentially by the distance of a school bus (weird unit of measure, but it translates for most cultures). This means that even if they NEED an answer to something, they will probably make a guess and keep working (on possibly the wrong assumption) until the next time they see that person. With this data, you start to realize that next door offices aren't the same as two people in the same room (and that there is a difference when those offices have doors next to each other vs. 6 feet apart).
So this post focuses on communication instead of co-location, but the two are tightly tied together since communication is one of the main reasons for a team room. I know that co-location isn't always an option, so we need to adapt to the next best solution when possible. The point is not that non-co-located teams fail; it is that co-located teams are faster and more productive.
Final thought: Putting the right people together in a distributed fashion will always beat the wrong people together in a co-located room.
Follow-up note: Recent post on the "secret sauce of offshoring" posted on ASD.