From Lydia Davis’s insightful and entertaining essay “Some Notes on Translation and on Madame Bovary,” from issue 198 of The Paris Review—
The quality and nature of a translation (let’s say from the French) depends on at least three things: the translator’s knowledge of French language, history, and culture; his or her conception of the task of the translation; and his or her ability to write well in English. These three variables have subsets that can recombine infinitely, which is why one work can have such widely differing translations. Publishers selecting a translator seem to proceed on the assumption that the most important qualification is the first. “Let’s ask Professor X, head of the French department at Y!” Often they completely ignore the second factor—how will Professor X approach the task of translating?—and certainly the third—what is Professor X’s writing style like? All three factors are vital, but in many instances, if one has to rank them, the third—how well the translator writes—may be the most important qualification, followed closely or equaled by the second—how he or she approaches translating, and it is the first that comes in last place, since minor lapses in a knowledge of the language, history, and culture may result in mistakes that are, in a beautifully written, generally faithful version, fairly easily corrected, whereas a misconception of the task of the translator and, worse, an inability to write well will doom the entire book through its every sentence.