The value of Business Architecture.

First of all, I don’t particularly like the term architecture since it implies something more static than what business and enterprise architecture is (or at least should be!). I think “engineering” or even better “evolutioneering” would be preferable, but I am not in the business of coining those annoying buzzwords. From this it is probably clear what I consider the function of business and/or enterprise architecture. It is a set of models to help us describe the current organization in easy-to-grasp terms to help describe, communicate, share, and develop understanding of our organization, its goals and efforts, and to help inform high quality decisions about technologies, but within a rich, relational, and useful context.
Let me provide a working definition of both these terms.
Business architecture is responsible for describing, through a series of models and definitions, what the structure and relationships between the different parts of the organization are. This includes business models (e.g. business model canvas) business capability maps, goals, strategies, business plans, etc.
Enterprise architecture is responsible for describing through a series of models (business capability maps, app and tech portfolios, enterprise data model, heat maps, road maps, etc.) and definitions, the structure and relationships of applications, technology platforms, data models, processes all in relation to the business capabilities.[1]
Now that we have some of definitions taken care of, what, if anything is the worth of business and enterprise architecture?

Let us consider the decision and execution layers of the organization, and to understand that we need to quickly remind ourselves of what strategies and capabilities are:
Strategy is the decisions of where, when, and how to engage with one's customers. It also includes the decisions, and discipline of what NOT to do.
Capabilities are the combinations of people, process, technologies, and information of how to execute the aspects of the engagement with the customer. E.g. Marketing, Product Management, Customer Management, etc.

In most organizations one sees the following layers (even if they are not formally expressed ):
Strategy – typically the executives, who are responsible for the decisions of where and how to engage with our customers (e.g. decisions which product/market mix will help us achieve our goals);
Management – typically managers and/or team leads, etc. who are responsible for directing the operations of a capability (e.g. marketing to ensure customers are aware of our products);
Operations – people responsible for executing the functions of the capabilities (e.g. copywriters, designers responsible for developing the appropriate material that will resonate with the target audience, campaign development, etc.)
Business architecture definitely falls into the strategy function, while enterprise architecture fits better in the management layer. (Enterprise architecture is virtually impossible without context provided by business architecture.)
 
In the asking of the “worth” question, it seems often to be implied that it has to be a currency answer. It is virtually impossible to answer the question in this way, any more than one can answer the question about the worth of strategy and management.
How much is it worth for an executive to know how her/his organization is structured in terms of capabilities, strategic priority, maturity, and transformational opportunities? How much is it worth to know that we can improve business performance through integration while reducing complexity and cost, making us more responsive to a changing market and customer expectations?
How much is the set of models worth through which the executives, managers, and professionals can develop not only a shared understanding, but also a shared goal, a close-knit team working together with the same purpose?
That is the value of business and enterprise architecture.


[1] In some organizations the term enterprise architect is used to describe someone who is responsible for a platform, or a set of technologies related to a particular domain, technology or business. Perhaps domain or platform architect to describe these roles (as some organizations do) would be more accurate.