Many non-technical people like to look at things that already exist and interpolate or extrapolate. "Well Facebook does this", "well I can buy GTA 5 on a shelf

Many non-technical people like to look at things that already exist and interpolate or extrapolate. "Well Facebook does this", "well I can buy GTA 5 on a shelf at Walmart for $60 (or something)", "people do this, I see it" and they have no idea of the level of effort and investment behind these things, they assume because it exists and is affordable you could erect something competitive or some similar feature set for marginal cost. Under managing expectations, you need to have a little heart on heart and try to bring some reality to the ideas. People don't come up with ideas in a vacuum, they look at inspiration from examples, connect things, add/remove them, and mutate them. I've also worked with a lot of engineering disciplines outside of software and people think because something is virtual in nature (it is "just software") it's significantly easier or cheaper than doing things with real physical capital. That isn't always the case. They also assume it's significantly easier in general, it's not civil engineering and you're not building bridges. Sure, you're not, and software isn't as commited as concrete in some senses but that doesn't mean erecting it or changing it is free, as designing and altering design for a bridge isn't free either. In the past year I've has someone handwave a theoretical issue as "it's just math" to some underpinning needed that has essentially remained an unsolved problem in mathematics for 60+ years... I could go on... but the most important aspect is to talk through the ideas and try to find any empirical evidence you can to get people to understand the level of complexity, scale, and amount of capital groups commited to make something they think is trivial and only need a handful of SWEs and a few months to throw together as if it were a PowerPoint that can handwave reality away.