Having never started a startup, I wouldn't know, but how long does the average successful startup go without hiring more people? The number of founders pretty clearly only matters during that period. And, is that the hardest part of getting a startup off the ground? PG wrote that he generally hired people when none of the people already at the company could do the job themselves. Seems to me that if 3 people have incredibly much trouble communicating, you'd have a similar amount of trouble once there was too much work for two people and you had to hire another one.

What's different between the very earliest stages of a startup and the stage where you've hired one person?