As stated earlier, the ability of systems design (and systems test) to reduce transdisciplinary complexity/ complicatedness when making new products or platforms, is one of the most important ones in product development. If this is not done correctly, it is easy to end up with just a system sketch (more like a jigsaw puzzle) and not a system architecture, see this blog post for a deep-dive how to be sure to not get it wrong.
A resulting system architecture is a also necessity for us so we can get an overview and understanding what we are doing and how our system actually looks like, which is also an important complexity to reduce, especially regarding development of bigger products. The system architecture therefore gives us the needed structure and overview, as well as how the parts fits and interact with each other, from our first thinking to a ready product. A very big product (system) can also need sub-system architectures, which means systems design per sub-system as well.
Here is an attempt to explain why reducing transdisciplinary complexity/ complicatedness is so important in order to achieve a proper system architecture:
The specified requirements on the respective parts, to be able to fulfil their respective functionality, as well as their respective non-functionality, i.e., the parts’ interactions to become a unified and well-functioning whole, all in order to fulfil the specified functional and non-functional requirements on the whole, can never be set in advance when we have transdisciplinary complexity/ complicatedness. This is what is meant with transdisciplinary (integrative) complexity/ complicatedness; we cannot specify the solution of the respective parts from start. Instead, we need to integrate the parts (from a well-informed hypothesis) to a whole, and verify and validate the whole, in order to see if our assumption or hypothesis, the systems design on the whole including the parts, were correct. And regarding this reduction of transdisciplinary complexity/ complicatedness, there is no difference between hardware and software. Reducing transdisciplinary complexity/ complicatedness often means prototypes in order to gain new knowledge from the tests on the integrated whole, until we have all the knowledge needed for developing our product. This is very different from disciplinary complexity, often called research, which is about digging down into a discipline in order find new science or new technology, and therefore mostly is a part of the way of working for hardware. But, as this also is about reducing complexity, reducing disciplinary or transdisciplinary complexity has one thing in common; we do not even know if we will find what we are looking for, and if we find it, we will not know when.
So, we can never fully specify the requirements for the subsystems (parts) when having high transdisciplinary complexity, since it is impossible to have that knowledge in advance, which is what Alicia Juarrero  explains as trying to reach new cohesiveness. This is why all new product development, no matter domain, is highly transdisciplinary complex. Simply, we can only achieve new knowledge at the synthesis (integration) of the parts to a whole, which also includes the systems tests of the whole, since we can never specify us out of any complexity. This can be seen as necessary iterative experimentations, but from well-reasoned hypotheses continuously updated. By that approach, we are able to gain new knowledge, so we can reduce the transdisciplinary complexity (unpredictable) to transdisciplinary complicatedness (predictable), before starting an initiative.
Making a new platform is also highly transdisciplinary complex. This is also valid, when we for example are combining different existing monoliths (some kind of disciplines), to a common modular platform instead, since we only have the disciplinary science and technology for each monolith. This makes the new platform a novel product (system), since the new combination, i.e., putting all the non-functional requirements for each monolith together, means that the new solution is novel. Put another way it means that, we can never aggregate the respective solutions of the monoliths to a whole, even though we can aggregate their respective non-functional requirements to the full non-functional requirements for the whole.
Changes on an existing product or variant of it, instead need only exploitation which means reducing transdisciplinary complicatedness. This means that the results from a few prototypes analysed by experts, will give us the needed knowledge so we can do the necessary final updates, integrate, verify and validate to a unified and well-functioning whole. This is why an iterative approach with prototypes as a solution to this, are self-evident in hardware product development, an integral part for us humans, since probably hundreds of thousands of years, in “hard” domains when reducing transdisciplinary complicatedness. These iterations can be seen as exploitations, but from well-reasoned hypotheses of course, to be able to gain the last needed new knowledge, and by that approach, reducing transdisciplinary complicatedness, still iteratively, until the product is finalized.
We end this article as we started, with stating how important the ability of systems design is, since reducing transdisciplinary complexity/ complicatedness, is key when we are developing new products in any domain; software and hardware, as well as building, bridges, etc.
Next article in the series about SOSD, is about the need of virtual delivery structures in product development.