[mbh]

When I read the book and this post, also reading almost all the comments here, I feel like one can just build a survey with direct questions about the assumptions and beliefs and get answers. Why even elbow grease? or do anything else?

Is it that users need to be in the "situation" to really give you correct data driven instinctive answer? While if you ask them a set of questions, the answers might not be correct or they might not answer?

[wpietri]

You've got it right. People say a lot of things that aren't true about themselves. Especially when you're asking them hypotheticals. Surveys have their uses, but they are not proof.

The only solid evidence that you have a real business is that you get money from people for something you did for them. So you get that evidence with the smallest experiment possible. That's the MVP.