Why is our voter turnout lower than the rest of the world?

Why is our voter turnout way lower than the rest of the world?
- Many democracies have proportional representation
- Some countries have mandatory voting
- US votes far more often than other countries
- Some countries have the day off on election day

Would it be better if we had better turn out? Hourly workers are in much worse shape when it comes to voting. At the end of a work day you have incredible lines in an urban area.
Would forcing them to vote? Make them more educated about politics-PROBABLY NOT