Seems to me that is the million dollar question. I certainly don’t have a definitive answer.
But if I were to hazard a guess, atmo, designers tend to be myopic and have over inflated egos.
The myopia limits designers in scope. I don’t need continuing education on ripping a hot sketch or CAD short cuts or modeling techniques. But I do require more knowledge about the overall new product development process. How strategy, branding and even things like supply chain management impacts industrial design. I was at a medical conference where they had game designers speaking to behavior change. They had no problems looking outside. But a lot a designers are stuck talking about looking at that clean line. Almost afraid to look outside. Quite ironic, atmo. And if I hear one more word about the genius of Dieter Rams or whoever the designer du jour is today, I’m going to wretch.
The ego problem contributes to the myopia. Since the whole world revolves around design, why bother with anything else. Also, the ego makes them think what they do is the secret sauce that can’t be shared - it’s special. Well, I’m here to inform you it is not. What you are doing is not rocket science and is most definitely not a trade secret, get over yourself. And the notion that your product has some life-changing emotional impact on people is just sad.
Straightforward enough?