In a sense every product business on Earth can be broken down as "you need to cover your monthly expenses, you convert at X%, so you need N people in the front to N*X dollars."
Thing is, that's true of both the companies who are successful and those who aren't. So that in itself is true but unhelpful. It's like saying "Human beings need to eat or else they'll die." Yes, but everyone dies whether or not they eat!
So the real question is: How do I get quality traffic? How do I develop a product people actually want? How do I separate myself from competition? How do I market without spending too much money? How do I get happy customers to tell their friends? How do I get the media to give me free marketing?
Of course these can't be answered in one go, because they're the fundamental questions of all companies...