I believe that each citizen has the right and responsibility to determine whether he or she is fit to vote, and not to vote if they determine that they cannot do a good job of it. But there should also be a preferential option in favor of voting; and the best argument ever made on the subject is, I think, this beautiful speech by Calvin Coolidge. The whole speech is great, but I especially like this paragraph:
But the right to vote is conferred upon our citizens not only that they may exercise it for their own benefit, but in order that they may exercise it also for the benefit of others. Persons who have the right to vote are trustees for the benefit of their country and their countrymen. They have no right to say they do not care. They must care! They have no right to say that whatever the result of the election they can get along. They must remember that their country and their countrymen cannot get along, cannot remain sound, cannot preserve its institutions, cannot protect its citizens, cannot maintain its place in the world, unless those who have the right to vote do sustain and do guide the course of public affairs by the thoughtful exercise of that right on election day. They do not hold a mere privilege to be exercised or not, as passing fancy may move them. They are charged with a great trust, one of the most important and most solemn which can be given into the keeping of an American citizen. It should be discharged thoughtfully and seriously, in accordance with its vast importance.