I'm against mandatory voting - In my opinion it is the duty of a concerned citizen to vote at least as a blank vote if you're against the system, however I don't think coercion is the answer - I do think abstention is troublesome specially in Europe, but mandatory voting is not the answer. Brazil is an example of mandatory voting. One of the main arguments, in my opinion, against mandatory voting is that ignorant people who aren't concerned with the system will inevitably vote poorly and sometimes extremist parties gain votes
Whoever fights monsters should see to it that in the process he does not become a monster. And if you gaze long enough into an abyss, the abyss will gaze back into you