For a good literary translation you need someone who has mastered both languages and is a good writer as well. The pay you get does not match the skills needed. It is often done badly.
This I think is only a part of it.
But there is more to a good translation.
For example there are sometimes events or naming in a book, which the author knows will have meaning later, thus the exact wording he chose to lead to misinterpretation. Now there are several ways to translate that, depending on the language you are translating into, depending on words and phrases available in said language due to cultural and historical differences.
The translator can be perfect in both languages, can be an extremely skilled story teller, but still make a poor choice in translation, just because he is not the original author and does not know what is to come. Or that there is more to it, than it seems at first read.
Then there is the IMHO not unimportant fact, that one would not only translate works one can relate to or enjoy, but also stuff you think boring or bad writing. So your heart wouldn't be in it, so to speak.
Then there are words and phrases that sound good in one language, but weird in another. But you would want somehow to convey the feeling they produce without changing the meaning.
I tried that with some wordings I wasn't content with.
Like JB for example:
This only true for the DF, not Alera or Cinder Spires (I haven't read that yet).
He writes mostly like some dude telling his story with mostly simple word choice. Mostly I feels as if Harry was just sitting there with his beer and telling his story to a friend. But this is exactly the art in it. Sometimes his sentences are so minimalistic that you could not honestly call them sentences. But sometimes they are almost philosophical. Like the main person himself.
I tried to translate specific parts for myself and my friend who asked me about parts she wasn't sure if she understood the meaning.
It is easier with the long complicated sentences. But really hard with the short ones. Especially to create the intended feeling.
I can only remember two of them. But I can't look up the translation of the first one because the German book belongs to the library. It was in Proven Guilty, the elevator scene: "Stab. Twist."
I couldn't find a satisfying translation myself. What was done conveyed the meaning, one would not have noticed if one didn't know the original, but I remember, it was too many words.
The second one was in Changes, after he killed Susan.
I used the knife.
I saved the child.
I won the war.
God forgive me.
(It may not be correct, I'm doing this without looking it up, because at the moment I only have the translation at hand)
This was not translated the way I liked. Though the translator used the same style: short sentences, each it's one line.
So no matter how skilled you are, it is still not possible to do a perfect job. This is one of the times it could have been translated almost word for word, but he didn't and thus ruined it.
Don't get me wrong. It wasn't ruined for a first reader who didn't know the original. I remember my friend sending me exactly this part and telling me she needs to pause because she has to cry and can't see properly.
But I was disappointed.
On the upside: there were times, the translation made me understand something better. When I thought, Oh that's what he meant! I thought it was something else.