When teaching Entrepreneurship at NITH this semester, I am leaning quite heavily on Steve Blank's book The Startup Owner's manual (as a supplement to Business Model Generation by Alex Osterwalder, that is our main course book in addition to articles etc.).
One of the key phrases I particularly like in Steve's book, in addition to the definition of a startup as a temporary organization searching for a scalable business model, is the advice to get the heck out of the office (there are no facts or customers in there!).
Even if "the office" might be a metaphor for many startups, there are no subsititutes for actually testing hypotheses on customers.
So do I practice what I preach? Well, I try to - with tapbookauthor.com (and Norwegian variant epekebok.no) now up in low-fi version 0.5 to start describing our awesome app publishing/authoring tool, we are ready to get the first set of post-pilot customers! Next week we are demoing for potential customers and starting discussions with seed investors - getting (the h***!) out of the office...