I graduated from college at 20 and became a tech investment banker. In hindsight, it was a terrible decision but I simply didn't know any better. Tech crashed in 2001 so a lot of my engineering friends went into finance and I simply followed them.
I learned two really valuable lessons from the experience: one, if you don't build your dream then someone else will hire you to help them build theirs; and two, I learned what really mattered in life after I lost it all from working all the time. Hint, it's not money or fame.
The simple truth is that the public markets place a premium on growth. For example, plot a graph of growth rate on the x-axis and revenue multiple on the y-axis for all public enterprise cloud companies. You will see a direct correlation - higher growth leads to higher trading multiples. That's why startups prioritize growth over profitability. Now this only applies to startups which scale to the point of going public. I think Fred's points are valid and apply to the vast majority of startups (that won't go public). Food for thought.
My personal favorite is "Speed is the essence of war. Take advantage of the enemy's unpreparedness; travel by unexpected routes and strike him where has taken no precautions." To me, a startup's major advantage over incumbents is speed - speed of product iteration and speed of decision making.
I learned two really valuable lessons from the experience: one, if you don't build your dream then someone else will hire you to help them build theirs; and two, I learned what really mattered in life after I lost it all from working all the time. Hint, it's not money or fame.