The most efficient and effective method of conveying information to and with a development team is face to face conversation.
Since there are so many misconceptions about miscommunication around agile, I created my business cards to contain the entire Agile Manifesto so that when people confuse scrum framework with agile philosophy or say, “This is agile blah, blah, blah,” I can hand them my card and say, “This is agile.”
Then I let them know that agile is nothing more than a philosophy, a series of values and principles.
In my mind, a principle is something that could be debated. When it comes to methods of communication, it would be very difficult to debate that something other than face-to-face conversation is best so this reads more like a fact than a principle.
A quick google search on the topic produces a lot of results in confirmation that face-to-face communication is “the gold standard of communication” and an impressive body of research demonstrates that face-to-face is the most information-rich medium.
The question is why this would need to be called out in the Agile principles? I think the reason is that all too often software development companies forget this important fact.
I point out in my presentation about complexity and Cynefin that most software development is complex. As such it requires a great deal of communication and collaboration. It is not something that we can just gather requirements and parse these out to large and disparate teams across the globe (unless, of course, your project is truly complicated and not complex).
Working in an Agile way requires that we come to a good understanding of what is desired through frequent, high-quality communication. The fourth principle addresses the frequency while this principle attends to the richness and quality of the conversation. I always tell my teams that they need to make sure to keep some whitespace free on their whiteboards since the most effective communication is face-to face at a whiteboard so that ideas can be discussed in all the richness of our senses and where examples can be used to quickly iterate through ideas.
In the end, all the agile principles and values must be viewed through the lens of being a reaction to the mistakes that were perpetrated before. It is readily apparent that this principle was added to the other eleven to be a constant reminder that documentation and CYA only allow us to avoid failure, but real face-to-face conversations lead to a much deeper understanding that will (hopefully) lead us to success.