Ask HN: Engineers and visionaries, what are your challenges with each other?

Over this past year, I've been putting together some thoughts on what it takes for an engineer to effectively work with a visionary. I understand that there are a lot of blurred lines, but I'm approaching from the extreme ends of the spectrum.

If you're a visionary, what do you often see as hurdles when working with engineers? What are the frustrating or colliding issues that cause a project to halt?

If you're an engineer (builder, strategist, implementer, scientist), what have been your challenges when working with a visionary?

What elements of the dynamic between these two spectrums are most interesting to you?

(Okay, I know I asked three-in-one, but hopefully this will look more like a discussion than a Q&A.)