Design is constraint

A famous sculptor was asked how he makes such realistic sculptures. He said 'I do not make them I merely remove the unnecessary pieces from the rock'. 

Design is often looked upon as an innovation that was created without any constraints. It seldom is the case. Where there is a good design there is bound to be a set of constraints imposed on the system. 

When traversing the design approach as an architect I find business operating model lays the first level system constraint followed by the data that is required to effectively run the business processes associated with the operating model. The data needs determine the applications that need to be put in place. The applications determine the infrastructure requirements. So, the design constraints imposed by the business, process, data and application define the design of IT systems and infrastructure.

It might also happen that infrastructure puts constrains on the business model. This is when business design is constrained by existing infrastructure a.k.a., execution driven design constraint as opposed to a by-Design model. 

This is always a trade-off as an architect I've had to consider in being Strategic or Tactical.

Drawing back to the example of the sculptor, the design choice is between something new and an improvement on something existing. The path of least resistance usually comes from eliminating wastage and improving the situation rather than overdoing things by bringing new solutions that override existing ones.