Are your villains too sympathetic?

I find unremittingly evil villains boring. Take Voldemort, for instance - what does he get out of life, what motivates him? What does he do in the long winter evenings? He must, surely, get fed up with thinking up ways of being nasty to people and gaining world domination 24/7. Doesn't he ever fancy going out for a pizza and a film?

I tend to err on the other side. In my first novel, Torbrek...and the Dragon Variation ,  the baddie Skardroft became so sympathetic I had to introduce a further baddie, Corfe, who as a torturer was hard to like. But I have to say, in the sequel, I feel sorry for Corfe as he attempts to continue his evil ways after suffering well-deserved head injuries...

There is an interesting discussion on this topic on Kindleboards. The suggestions of how to make your baddie sympathetic, but still evil, are so insightful I'm going to quote them here:
My current WIP is a fantasy, and my villain became so cool, charismatic, and *sympathetic* that he was dominating the whole story! The problem was - I think - that we had too much of his POV.  We saw too much of his thoughts and related to him too strongly.  I went back and either cut his POV scenes, or rewrote them from another POV. And suddenly - voilà - he became scary again.  He's still a very charismatic villain, but he's clearly a villain. Sandra Miller
I always get into the heads of my villains and yes, their self-justification can be surprisingly effective. I wouldn't consider this a drawback, however. A richly drawn, slightly sympathetic villain is a wonderful detail to include in your novel. Michael Wallace
Sympathetic is fine; what is important is fear. The reader might understand and even sympathize with a villain but when that villain is in the same room as the protagonist there needs to be fear, uncertainty about what that villain might do. It's that fear and uncertainty in the heart of the reader that makes a villain effective and if the villain is also sympathetic that's even better. KM Johnson-Weider
To create a good villain, you have to be willing to completely, utterly, irrevocably damage the lives of characters you love. Otherwise, you're just having guys wave around guns with blanks instead of bullets. David Dalglish
The uncertainty has to be there.  I think what I need to do now is make something happen to throw the readers the other way again.  So you thought you understand this person? Think again! Several people have commented that it's best to keep the villain off-stage as well, at least initially.   The monster in the shadows is scarier than the one you can see, as long as you also see the bodies strewn around. Masha DuToitI think I'm getting better at writing convincing but dislikeable villains. One reviewer commented about Sir Peter Ellis in Replica: ' the oily and cold-blooded boss is totally believable'. That'll do me.