Living languages change over time. We all know that today´s English does not resemble Shakespeare´s English very much. We speak differently, spell differently, and assign new meanings to old, established words. Does anybody know what Hamlet actually MEANT, when he said "Get thee to the nunnery, Ophelia!"? Certainly not everybody, today. But in Shakespeare´s time, people understood.
My speciality is medical and computer-related terminology, and these are fields that have grown rapidly. New terms see the light almost every week, and since English-speaking countries are so dominating and since English is the primary international language today, English terms are invented, even if the inventors themselves might not have English as their native language.
Countries like France and Norway try to be quick in translating these new words into their own corresponding native terms, sometimes with ridiculous results.
Other countries accept the influx of English terms, and make only lame efforts at translating them. And many professionals working in these fields ignore these efforts and keep using the english terms. Such a country is Sweden.
Taking computer- and communications technology as an example, I have since a while back noted that there are two parallell worlds in Sweden; One world, usually consisting of the computer- and communications professionals, prefer the use of English terms, and sometimes do not even understand the Swedish terms until they are translated back into English. And the other world, consisting of the "non-professionals" ("laymen" or "common people" might be better terms here) which prefer the use of Swedish terminology.
Consequently, when getting an assignment to translate a technical article or manual into Swedish, one has to know who the customer is, and which are the people who are going to read the stuff.
One sometimes gets into illogal argumentations, such as translating "webmaster" into "webbredaktor".
Why "webb"? Because it then becomes consistent with Swedish rules of pronounciation.
Why is that necessary? "webb" is not a Swedish word?
Well, it is now!
How can that be? "w" is not included in the Swedish Alphabet! If you want to make a Swedish word out of it, you should spell it "vebb"!
And so on, not to much avail.
The bottom line here is; you have to make some kind of agreement with each and every customer as to what constitutes a proper translation. You have to know What kind of terminology the customer prefers, Swedish, English or "Swinglish". It is not always easy, and sometimes calls for as much diplomatical as translational skills.
Presumably, this problem arises also in other countries. And English terms are like weeds; when they come to areas where there are no native terms for the concepts they convey, they quickly take root and grow. And once established in the new region, they are not easy to weed out. If you are French, I´m sure you know what I´m talking about.
The translator´s job is certainly not to do any "weeding". The translator just "goes with the flow" and tries to stay tuned to what terms are used on a day-to-day basis. It is, therefore, rather important that translators which specialise in fields where new terms and concepts pop up frequently, stay in the country where their readers are. If they were to move away from their native regions, they might soon lose touch with how their native language is used, as regards these new terms.