The ideal translation...
is invisible.
All the rest depends
on the original.

Because, as Umberto Eco says, the art of translation is a serious one that requires constant patience and humility, but also and above all, a number of important decisions about the text to be translated from the final version in the source language to an entirely  new version in the target language, and the best way to do it.
The translator’s task is to transfer the source into the target language maintaining not only the conceptual content, but also the style, impact and even the ambiguity, if used purposely.
It is not enough for the translator to know the source language, she must also know the culture of the country in which the original was written, and, of course, the subject matter it deals with.
The ideal outcome is a text written as if the author had written it in the target language.