Rational ignorance

Rational Ignorance is a term most often found in economics, particularly public choice theory.

The cost of educating oneself about an issue sufficiently to make an informed decision can outweigh any potentential benefit you could reasonably expect to gain from that decision, and so it would be irrational of you to waste time doing so. This has consequences for the quality of decisions made by large numbers of people, such as general elections, where the probability of any one vote changing the outcome is very small.

See also: bounded rationality