Built in bias

One of the biases that people rely on when they make decisions is loss aversion: like in the insurance example above, they tend to overweight small probabilities to guard against losses. Even though the likelihood of a costly event may be miniscule, we would rather agree to a smaller, sure loss — in the form of an insurance payment — than risk a large expense. The perceived likelihood of a major health problem is greater than the actual probability of such an event actually occurring. We would all like to believe that we are logical decision makers. In the field of user experience, we often talk about how users weigh the expected utility of different alternatives to determine what action to take or where to go next.