People often complain about low voter turnout in the U.S., which has declined over time and is much lower than voter turnout in other countries. Notice at the first link that voter turnout in the U.S. has generally decreased over time, from greater than 60% in every presidential election year during the 1960s, to less than 60% in every presidential election since, and below 50% in 1996. The pattern is the same for midterm elections - voter turnout was close to 50% in the 1960s, and fell to below 40% starting in the 1970s. The second link shows that the U.S. ranks #120 (with 66.5% turnout) out of 169 countries in an international voting comparison by International IDEA.
Many people are upset by low U.S. voter turnout, but maybe they shouldn't be, and here's why: In almost all cases, higher voter turnout would NOT have changed the outcome of the election, and we therefore get the same election results at a lower cost to society, measured in the opportunity cost of our time.
Those who complain about low voter turnout almost never make the argument that higher voter turnout would CHANGE the outcome of the election; their position is usually that more people should vote for other reasons: to exercise our right to vote, to fulfill our civic duty, or to participate in democracy. But I have never heard anyone say "More people should vote because low voter turnout leads to unreliable results," or "more people should vote because that would change the outcome of the election."
Mostly, I think people would simply "feel better" with a 90% turnout, compared to having the same election results with only 40% turnout. But think about this - would you feel any better about a blood test if they took two pints of your blood instead of just 20 ccs? Probably not.
There are about 160 million registered voters in the U.S. From statistics, we know that a sample size of 16,639 would accurately and reliably represent the entire population of 160 million at a 99% confidence level, with an error of only 1%. What this means is that if the first 16,000 people who vote when the polls first open in the morning are random voters who represent the population of voters, almost all elections are already decided by 9 a.m. or so in the morning. The rest of the voters are really just wasting their time, in the sense that their votes will not affect the outcome of the election. It is like a blood test - the results won’t change with a larger sample.
Voting is expensive when measured in its full cost: our time. An hour spent researching the candidates, attending or watching debates, and waiting in line to vote at the poll (see photo above), is an hour lost forever doing something else. Therefore, a case can be make for low voter turnout, because the election results are almost always exactly the same as an election with high voter turnout. Low voter turnout saves our most precious non-renewable resource: our time, and therefore it is socially more efficient than high voter turnout. We should be proud of, not ashamed of America’s international ranking at #120 for voter turnout - it shows we're serious about conserving scarce resources.