In some countries and environments where the standard of spoken English is very high, authors may be expected to produce English versions of their own texts, even if for example they are scientists who have not specialized in foreign languages to a high level.
Unfortunately, writing accurate and up-to-date English is a different matter from speaking English fluently. Thus, an academic who wants a paper accepted for publication in an English language journal will need his or her text checking and correcting by a competent native speaker, which is what I mean by language correction. Similarly in a company or business environment it is common in some countries (Scandinavia for example) to use a translation agency staffed entirely by in-country translators. Inevitably the resulting text is riddled with errors and inappropriate expressions. The expectation in these situations may be that there will be just a few spelling mistakes or other minor details to clear up, but the reality is often that there are words and phrases in every other line which are ambiguous, unclear or incomprehensible, due to the author or translator over-estimating his or her competence or being forced to write at a language register much higher than that which s/he has ever been taught.
The language corrector’s challenge then is to make sense of the text by a combination of intelligent guesswork and ongoing dialogue with the original author, to ensure that the intended meanings are actually being represented.
With anything less than outstanding written English skills on the author’s side, it is usually quicker and cheaper in the long run to commission a translation from the foreign language in the first place, rather than to write it in the foreign language and then get it ‘cleaned’. However…. if your text is already written in English, and you are aware that it needs improvement, please send me a representative sample of 100-500 words and I will tell you what is wrong with it – and give you an estimate for putting it right!