For Google, I don't think it was certain at all that they would succeed and there was a real chance they could have failed. Their first business model was selling their search engine to enterprises via hardware boxes, which grew very haltingly.
In fact it wasn't until Google came across Overture's idea of selling advertising tied to web search results that they found the success they now have, and which they appropriated despite Overture's patent because they were so desperate to find a working business model.
Overture(later acquired by Yahoo) sued Google, and Google had to pay in stock worth hundreds of millions in 2004 (tens of billions now had Yahoo kept them).
So how does this relate to ProductHunt? Google had a real product, knew who their users were and put their experience first. ProductHunt has polluted their site with junk and allowed their voting process to be distorted, making it practically useless to anyone who came there to find great products.
See here: http://www.nytimes.com/2004/08/10/business/technology-google...