The right for an organization to exist is the added value it delivers to its surroundings. This is partially expressed in the business goals the company strives to attain. 

Working within architecture is validated by the achievement of those goals. The development of an architecture has to be driven by the business goals. 
Without this principle, there soon may be the rather vague situation of “architecture for architecture's sake.” This means that during architectural development, the focus should be on achieving the business objectives rather than on autonomous development of enterprise architectures. 
This is also the reason DYA applies the “just in time, just enough” principle.