People get very excited about their idea for their start-up. They’re supposed to, that’s why they are doing it.
And they get that they need to be solving a problem, meeting a need. They have read “The Rework” and often they are trying to solve their own problem, which is good.
Only, when I ask them what the market is, they often say “Hey, me and my mates think this is cool and we totally need this. There are loads of people just like us, so the market will be huge”.
But it’s not. You and your mates are a group of similar people with similar needs, wants and view of the world. That’s why you are mates. There’s no reason why anyone else in the world will want what you want. In market research terms, you do not represent a statistically significant sample. No matter how many friends you have on Facebook.
(And asking your families doesn’t make it any better. It’s still not enough, and they’re inherently biased anyway).
Like Steve Blank says, “Get out of the building”. Go and find out if anyone else cares before you waste your time building it.