I and my partner started Naught Dog, Inc. from scratch (some various articles I've written on this here http://all-things-andy-gavin.com/video-games/). We went from 2 (us) to well over 100 employees. Building from bigger and bigger game one at a time. But we started in a much easier era (the 80s).
I'd be interested to know your take on what made the 80s an easier era to start in. Is it mainly that the field is more competitive now than it used to be, or are there other factors as well?
A number of factors. Games were much smaller then and a competitive game could be done in 1-2 years by 2-4 people. The budgets were usually in the 5 digits. This made it much easier to do if you knew how. On the flip side, far fewer people had any programming expertise.
Now, it's possible to do something similar on the web, or with a cheap mobile game, but in console gaming (PS3, 360 etc) the games all run in the 8 digits (over $10,000,000!) and involve big teams, often over 100 people.