Flavored liquors like schnapps or Fireball. I mean, I can drink them just fine, but if I ever find myself in such a situation where I'm compelled to drink flavored booze, it just makes me question the choices I've made to arrive at such a depressing place. With so many excellent alcoholic beverage options available, something that tastes like artificially-flavored candy has absolutely no appeal whatsoever.
I'm also not big on vodka; what on Earth is the point of a spirit where the goal is to not taste like anything at all? I drink boozy drinks because they have a unique taste that is unavailable in soft drinks; there's nothing alcohol-free which tastes like a fine whiskey. You know what tastes EXACTLY like a vodka drink? Whatever the fuck you mix it with. It offers nothing except alcohol, and I'm not nearly enough of an alcoholic to want to get drunk without tasting anything.
I like a Pisco Sour or a Caipirinha, but pisco or cachaça on their own are pretty vile. And they really aren't used for anything outside of those drinks, so if you end up with a bottle, you're going to get bored of your options with 3/4 of the bottle left. You'll still get some good drinks out of it, but it lacks variety.