Besides all the arguments that has been already made somewhere in the depth of internet and anywhere else, I consider additional reason why I’m not voting – I think it is harmful.
It is harmful in couple ways – first of all, I think it would make me biased toward politics and people. Having in mind the person or fraction I vote for I could have problem to objective assess different opinion and so on.
Secondly, it could made me politically lazy. I put the piece of paper in the box, so leave me alone, I completed my civil duty. I think that there are so much more valuable ways to influence politics and social life in the country that voting is probably the worst way to improve anything.
Third reason – it would make you unhappy! Think realistic, when you’ve got only option between smaller and grater evil the final outcome would be always bad or worst. What kind of feedback for you it is?
If you don’t know other reasons, try search them in google, I can assure you there is lot more.
PS: Remember, vote from alcoholic homeless looser have the same value as the vote from university professor.