In an interview with Meg Pokrass, Daniel Handler rants against the idea of "likeable characters" in fiction:
Characters are in books; you’re not going to have lunch with them. Moreover, the best books are full of trouble, so the characters are either in trouble or causing it. Most people aren’t likable in such situations. ... It’s like saying that the great thing about Kind Of Blue isn’t Miles Davis, but the trumpet itself. Such a compelling instrument!
Thus, character is bunk. There is plot, and there is voice, and they conspire to create an illusion we call “literature.” It is a glorious illusion and a compelling one. When a writer tells me they’re worried about a character they usually mean there’s a flaw in the plot, or the prose just isn’t pulling things together.
(Hat tip: Kyle Minor)