It's not just linguistic distance. A good literary translator needs to really understand of the source material, with all of its cultural context and multiple possible interpretations, and somehow recreate the same effect in the target language.
This requires not only linguistic fluency but also a deep understanding of both cultures, as well as the literary traditions of both. If an English author makes a subtle allusion to a passage from Shakespeare, for example, how do you translate that nuance to a language that hasn't had Shakespeare?
I suppose it's much easier to achieve this between Dutch and English, than between Korean and English. The pool of people who move about freely between the latter is much smaller, for both geographical and historical reasons.
