I like to complain about the government.
I love quoting Mark Twain: "Suppose you were an idiot, and suppose you were a congressmen -- but I repeat myself."
Politics gives me ulcers. So why do I vote?
Because I value my right to complain, and my freedom to make snarky comments about idiotic legislation.
I may not like who gets elected every time, and I may not care for every law that gets passed by the guy I did vote for, and I may not agree with every action my country takes -- but I do like knowing my voice counts when the votes are counted.
I like knowing that I'm allowed to vote... and that I'm allowed to criticize my politicians when they majorly goof-up. Every day I have the right to voice my opinions to my friends, to strangers, and once a year to my government, at the polls.