Non-cheap ways to make villains evil?
Do you have any tried and true techniques to make villains of your stories truly hated by the audience?
I mean, frequently it's "eh, sure, that's bad, he's got to be stopped" but the audience would rather observe the villain more, learn, maybe try to get them to change their ways. Or worst of all, pity the villain in the end for failing to execute their just revenge, or not getting along with their plan for what would -really- be a better future, even if through baptism of fire.
Now what to do if you want the readers to wish the villain dead in worst way possible?
Of course getting the villain to kill one of most liked characters may work wonders here. Except it will definitely alienate the audience, it's cheap and disliked. It's something that will make the readers hate the villain and hate the author for writing the story that way.
Now what to do to have the readers feel a warm fuzzy when the villain gets hurt? A good healthy dose of schadenfreude? A good dose of ire when the villain gets away with their shenanigans? Make them love to hate that character, feel the story was written just right, no cheap gimmicks, and the villain is still really worth all their hate?
This all without loss of the basics: keeping the character fully believable and with completely logical (or at least sufficiently emotional) motives driving them, at least moderately competent and sufficiently interesting.