Much like with pure science disciplines, software’s history has been a history of discovery. However, while understanding is the object of discovery in biology or physics, understanding and engineering is often the basis for discovery in software. While software development is indeed the process of combining and assembling resources to manifest a given vision, deep understanding of the resources and all the ways to use them also inform the vision in a bidirectional relationship. It’s not always as simple as starting with a vision and then using the resources available to build it. They often emerge together or in an intertwined way, and things continually leap forward over and over.
And this is why software-engineering is so heavily based on prototyping.