"Let’s do the math. We paid webmasters 10 cents every time one of their users used our greeting card engine. We got paid up to $3 by venture-backed firms every time we got those users to register for these venture-backed firms’ services. That’s how we got our margins."
I think the lesson here is that making money on the internet is greatly facilitated when other people are willing to pay irrationally large amounts of money for what you're selling. Product quality may have played a role in this story, but it sure sounds like the critical step was recognizing the ridiculous inefficiency that existed in the market for eyeballs (i.e. paying $3 for something acquired for $0.10)