When a new technology appears, people usually think it will grow because it is better, faster, cheaper, or more efficient. But in practice, that is rarely what makes something spread around the world. What makes new things spread is trust. Airbnb didn’t grow just because it was cheaper than hotels. In the beginning, the idea of sleeping in a stranger’s house sounded absurd. What made Airbnb grow was a reputation system: reviews, profiles, photos, history. Before trusting the company, people s...

When a new technology appears, people usually think it will grow because it is better, faster, cheaper, or more efficient. But in practice, that is rarely what makes something spread around the world. What makes new things spread is trust. Airbnb didn’t grow just because it was cheaper than hotels. In the beginning, the idea of sleeping in a stranger’s house sounded absurd. What made Airbnb grow was a reputation system: reviews, profiles, photos, history. Before trusting the company, people s...