We humans tend to be apprehensive of change, which often leads us to make choices that guarantee that things remain the same, or change as little as possible. Needless to say, this has ramifications in everything from politics to economics. We like to stick to our routines, political parties, and our favorite meals at restaurants. Part of the perniciousness of this bias is the unwarranted assumption that another choice will be inferior or make things worse. The status-quo bias can be summed with the saying, "If it ain't broke, don't fix it" — an adage that fuels our conservative tendencies. And in fact, some commentators say this is why the U.S. hasn't been able to enact universal health care, despite the fact that most individuals support the idea of reform.
In cognitive science, choice-supportive bias is the tendency to retroactively ascribe positive attributes to an option one has selected. It is a cognitive bias. For example, if a person chooses option A instead of option B, they are likely to ignore or downplay the faults of option A while amplifying those of option B. Conversely, they are also likely to notice and amplify the advantages of option A and not notice or de-emphasize those of option B.
Congruence bias is a type of cognitive bias similar to confirmation bias. Congruence bias occurs due to people's overreliance on directly testing a given hypothesis as well as neglecting indirect testing. Peter Wason attributed this failure of subjects to an inability to consider alternative hypotheses, which is the root of the congruence bias. Jonathan Baron explains that subjects could be said to be using a "congruence heuristic", wherein a hypothesis is tested only by thinking of results that would be found if that hypothesis is true. This heuristic, which many people seem to use, ignores alternative hypotheses.
Status quo bias is an emotional bias; a preference for the current state of affairs. The current baseline (or status quo) is taken as a reference point, and any change from that baseline is perceived as a loss. Status quo bias should be distinguished from a rational preference for the status quo ante, as when the current state of affairs is objectively superior to the available alternatives, or when imperfect information is a significant problem. A large body of evidence, however, shows that status quo bias frequently affects human decision-making.
Status quo bias interacts with other non-rational cognitive processes such as loss aversion, existence bias, endowment effect, longevity, mere exposure, and regret avoidance. Experimental evidence for the detection of status quo bias is seen through the use of the reversal test. A vast amount of experimental and field examples exist. Behavior in regard to retirement plans, health, and ethical choices show evidence of the status quo bias.