Over the course of my career I've had the opportunity to lead or be in the audience for dozens, if not hundreds, of technical demonstrations. I would assume that this is actually fairly typical for many engineers in the tech industry, and yet despite this, so many in our field find the act of leading a demo to be difficult. Even if you haven't had to lead a demo, it is quite likely that you have at least sat through a bad demo. Maybe the speaker was not engaging, or maybe it was uninformative, or most likely the product just didn't work.
So why are technical demonstrations, something that is so common in our industry, so hard?