This holds true on or off the web, you can have the best and cheapest product in the world, but unless you have a persuasive sales approach no one is going to buy. Cool web sites do not sell. Persuasive web sites sell products. The cooler the site - the more people reacted. The basic premise of persuasion is emotions.
People buy for emotional reasons and justify it with logic.
You have to give them both, stir up their emotions and justify the sale with facts. Works every time. Has for hundreds of years. People buy from people they like. They don't buy from companies or web sites.