Oh, that just means I happen to write in clear, unidiomatic English ;-). Add just a smidgen of irregular usage, contemporary metaphors and such and things can go South pretty quickly.
That'll just be a training problem (often translation is driven from example texts that have lots of translations, and we have many of these for multi-national orgs like EU, which necessarily don't include a lot of colloquialisms), and the inconsistency isn't found because the models built don't extend all the way out to real world experiences (training) and recognizing text as a real world experience narrative. I think a much deeper network could do better but we don't know how to train them, we take way too long as it is.