Compulsory voting
Compulsory voting is increasingly resented by citizens in some countries such as Brazil, the largest country where compulsory voting is enforced: at the last presidential election in 2014, some 30 million voters, about 21% of registered voters, did not vote, despite the fact that Brazil has some of the most severe penalties enforced against non voters.
Electoral systems of the Australian states and territories
Like all other states and territories voting in South Australia is compulsory, however unlike other states initial enrolment is not compulsory so a voter could theoretically not be compelled to vote if they chose never to enrol.