You're implying that a prototype is a form of communication, which I strongly agree with. I think the key thing here is to ask "What is the impact on other peo

You're implying that a prototype is a form of communication, which I strongly agree with. I think the key thing here is to ask "What is the impact on other people if I just do the thing?" In the case of building the prototype, its either "Well, now they need to spend time looking at the prototype", which would be the case no matter what communication medium you used or its "Well now JS spent 4 days doing that instead of what was on the roadmap. On the other hand, we have a prototype of X" which is a bit of a gamble and depends on what people were depending on you for.