Actually, I have thought of something I 180'd on. I used to believe that not voting in any major election or referendum could only be the result of stupidity, a lack of appreciation for the value of the vote, and laziness. 

However, at the time of the Scottish Independence Referendum, I had a friend who chose not to vote. This sort of astounded me; I knew him to be an intelligent, politically invested person. We'd had many debates about the referendum. And the very concept of actively choosing to abstain from voting befuddled me. 

He explained to me that having looked into both sides of the argument in vast detail, he simply could not decide which side to vote for. He felt facts were being muddled by both sides, and that neither had substantial enough a case to convince him. He actively chose to abstain, saying he felt it was irresponsible to vote for something he had no conviction in - it would be an abuse of his vote, cheapening its value. I found myself rather agreeing with his reasoning. Although in that referendum I had a strong opinion and thus voted, recently I chose to abstain from a vote myself. Complete shift in my view.