At the risk of being accused of blowing smoke...
Engines, if I may:
I think your last post is the best sub-1 page summary I have ever seen on the fundamental reasons behind the need for a proper role-relatable design process.
In particular, what "airworthiness" means in context. Also, the essential symbiotic relationship between pilots and engineers within the design & airworthiness domain is superbly well described.
When I am King, I'll put the contents of that post on the walls of every room and corridor in ABW (and, if truth be told, in a few Test Squadron and T&E engineers' offices as well.)
Smoke off, smoke off, GO!