Why is it so hard to get the challenges of software-development across to people who are not from "our field"?
To be quite honest: I don't know. But I do have an inkling about some of the more obvious points. One of them, that has been pointed out numerous times, is that we tried to compare software-development with production for a really long time - instead of comparing it with, well, development.
But let's not linger on that aspect - let's look at another one that has not been covered quite as well. Language and mental models. In most other fields the words and their physical representations are put to the test quite early - even if the words themselves may be ambiguous. No one would really try to use hazelnuts or walnuts and cross-bow bolts when a manual speaks of "nuts and bolts".
So, what's different in Software development? A lot! One of the main differences though is, that we don't work with concrete material (nuts and bolts) but with concepts - words representing things from the physical world. Or even worse: words representing things from the physical world that represent concepts that represent intangible things - like money or time.
But let's just focus on the words for a second - they can mean a lot of different things to different people. For example my grandmother has quite a different notion of the concept "button" than my godchild does, as I am sure you can imagine.
Or, as Lewis Carrol put it in "Through the looking Glass":
'When I use a word,' Humpty Dumpty said, in rather a scornful tone, 'it means just what I choose it to mean — neither more nor less.' 'The question is,' said Alice, 'whether you can make words mean so many different things.' 'The question is,' said Humpty Dumpty, 'which is to be master — that's all.'
And this is not only true for the concepts we use inside our craft but also for the concepts we employ to create, envision and define our products.
Let's just look at some examples...
A Retrospective can be a very interesting art exhibition (for example on Ansel Adams) - or a very formal technique to optimize the way people work together.
And so forth...
So from my point of view one of the challenges we face is in the meaning we put in words and concepts and how much they can differ across organizations or even within a team.
What to do about it? Take the time to find your own meaning for the words, join industry groups to discuss those meanings and get a little bit better applying the concepts every day. And never rely on a word meaning what you think it means - always verify with the people with whom you're working, that you're talking about the same things - even if you use different words.
Shameless plug: And perhaps attend some trainings where you can experience some of the concepts behind some of the words first hand...