Although the reality of these biases is confirmed by replicable research, there are often controversies about how to classify these biases or how to explain them. Some are effects of information-processing rules, called heuristics, that the brain uses to produce decisions or judgments. These are called cognitive biases. Biases in judgment or decision-making can also result from motivation, such as when beliefs are distorted by wishful thinking. Some biases have a variety of cognitive ("cold") or motivational ("hot") explanations. Both effects can be present at the same time.
There are also controversies about whether some of these biases count as truly irrational or whether they result in useful attitudes or behavior. An example is that, when getting to know others, people tend to ask leading questions which seem biased towards confirming their assumptions about the person. This kind of confirmation bias has been argued to be an example of social skill: a way to establish a connection with the other person.