[junko]

I think it also depends on the type of startup you have, and how confident and knowledgeable you are of your target market.

I'm currently reaching the end of the ideation phase, and although I'm familiar enough with my target users, I plan to spend a few months in Asia (where they are) to test my assumptions - hidden and conscious - and see if I'm missing out anything else. No matter how careful and smart your assessments are, ultimately it's all in your head! So yes you're right, we need to be wary of false positives and make sure that we really understand our users. But launching fast is a pretty valid idea too; personally it would be a wasted opportunity if I go on the trip without anything to show! A simple prototype can be more powerful and a much better conversation starter, plus the further advantage of lighting the fire under your bum. That would close the catch 22 loop, I hope.