Thanks, but I think I must have not made my point effectively. I'm well aware that we have biases and being burned can make one avoid something "illogically". But if you are trying to sell something, then emotional appeal contains shorthand, dense information. As an example, see edw519's post in this same thread and the remarks of his he linked to: http://news.ycombinator.com/item?id=2372514 In short, he says he wants someone "shaking with excitement" to use his product. "Shaking with excitement" conveys a great deal of info about the value of the product with very little effort. If you can sum up the value of your product so succinctly and powerfully, then there is a kind of density of info of the sort that influences decision-making (ie leads to sales).

Does that make more sense?