I do think it's funny when the translator makes a point of shitting on other translations in the foreword. I think the version of Aristotle's Politics I read in college did that.
At least for "Norwegian Wood", I found the translation to Norwegian to "feel" better than (the excerpts I've read) of the English translation. It's hard for me to say if that is because Norwegian is my first language, and I learned Japanese from living in Japan, or because there are some parallels between terse Nordic prose and poetry and Japanese. I could certainly see the Nordic sagas working "better" in Japanese than in English.
But another reason I could see to re-translate something besides previous translations being flawed is them being old. If a particular obscure work only has on English translation, and it's 100 years old, it seems pretty reasonable to want to translate it into more modern English.