In Australia, citizens have a duty to pay taxes, defend their country (if required to do so), serve on a jury (if their name is drawn), and vote. That's the cost of living in a democracy.

If voting was compulsory, only lunatics would vote. I wouldn't voluntarily pay taxes, sign up to fight a war, or serve on a jury either - I'm not crazy; but I think it's important that these things get done.

One argument is to stop efforts to disfranchise voters. If voting is mandatory things like photo ID law in US won't fly (or at least would be much less effective). It also affect who politicians pander to. These days common strategy is to pander to radicals because it's easier to get them to vote. That would disappear if everybody has to vote.

When "none of the above" wins, it usually means new elections where all old candidates are banned or some other procedure to resolve complete distrust to current politicians.