In his TED talk Start With Why, Simon Sinek argues that what differentiates successful companies and individuals is that they don't simply have a great product to sell, they also understand why they do what they do:
"What you do simply serves as proof of what you believe. People don't buy what you do, they buy why you do it."
Sinek argues that when hundreds of thousands flocked to Washington to hear Martin Luther King speak, none of them went to see him. They went for themselves, because his "why" resonated strongly with their own. He didn't say "I have a plan", as so many politicians do. He said, "I have a dream".
Similarly, we shouldn't try to sell a product by enumerating the great things it can do. We should explain why we built it, what we believe, what kind of person or company we are, what problem we set out to solve.
Our emotions are more powerful than our logical mind. Often, all our logic does is manufacture post hoc rationalisations for what our emotions have already decided. By appealing to those emotions first, we make it more likely that others will want what we are offering.