ANALOGY
A simple analogy can be demonstrated to show how two different disciplines can come together for the common good of a workable solution.
An airliner relies upon the pilot to fly the plane but also the ground support engineers to keep the aircraft airworthy.
Whilst it is essential for the pilot to have an understanding of the airframe, the engineering and the design of the aircraft, he does not need to have expert knowledge of these aspects because he depends on his engineers to make sure the aircraft can fly.
By the same token the engineers whilst having knowledge of aerodynamics, do not need to have expert knowledge on how to fly the aircraft because that is left to the pilot.
The common goal of the engineers and the pilot is to make sure the aircraft can and does fly, ensuring that it is efficient and profitable.
PROJECT MANAGEMENT