[purerandomness]

> haven't talked to many potentially users?

Any bad answer to these questions is a showstopper, yes. It's an indicator that this company is definitely going to fail.

In your example, not having talked to many customers is the classical Juicero approach: Build a solution, then search for a problem that this solution is solving.

Not talking to customers means not understanding if there is demand for something, and if there are customers who would like to pay for a solution. (Problems exist in markets where target groups are not used or not willing to pay for digital solutions)

If you're starting out, I highly recommend reading the blog of Amy Hoy and Alex Hillmann (https://stackingthebricks.com/) - they defend the idea to first go on a "sales safari" where you simply obvserve your target group, and then find a solution for their pains.

As a founder, you want to continuously talk to potenttial customers about your idea or your prototype: make them use it and perform thinking-aloud tests.

[shanwang]

Good points. But how many customers you talk to is enough? If I'm building a product for enterprise, is talking to one keen potential customer enough? For a first time founder, I can't imagine someone without much connections can get the chance to talk to multiple potential enterprise customers.

What about a product targeting the mass market, if I'm building a mobile app, is talking to a dozen friends enough? or should I pay for a market research which can reach hundreds of strangers.

Do you talk to customers with prototypes of the features or do you just have a basic skeleton and say 'what if I have this and that'?

I actually subscribed to Amy Hoy's mailing list but haven't checked it out for a while...