If startups only ever made what people already want, there would be nothing new.
There's no surefire recipe for introducing something new that people don't currently want because it doesn't exist, but that they will want once they see it. And there plenty of ways to screw it up, so that someone who comes after you with the same thing will take over the market.
Sometimes people don't want something until somebody else has it, and they don't even understand it until then. Especially someone in their peer group. The marketing may have explained it accurately, but people don't trust the marketing rhetoric, and brush it aside as the usual half truths and exaggerations that advertising is chock full of.
