The focus of this book is software architecture. Why would we want to mention communication and culture in a book around software, then? If you think about it, all software is written by people for people. The human aspect is prevalent and yet we often fail to admit it.
As an architect, your role won't be to figure out the best approach to solving a given problem. You'll also have to communicate your proposed solution to your team members. Often, the choices you make will result from previous conversations.
These are the reasons communication and team culture also play a role in software architecture.
In one of the early chapters, we've mentioned Conway's Law. This law states that the architecture of the software system reflects the organization that's working on it. This means that building great products requires building great teams and understanding psychology.
If you want to be a great architect, learning people skills may be as...