There are different types of translations, and different content requires a different grasp of the language and mastery of a certain kind of vocabulary.
For example, translating a poem would probably require the mastery of a language in a certain way, where as translating technical documents, such as pharmaceutical content, would require the knowledge of very specific technical terminology.
Technical writing and translation are specialised fields, and there are translation companies that have expertise in translating and creating scientific, procedural and technical content. Companies that need to produce technical material in different languages usually get it done from such translation companies.
Technical writing also requires certain intrinsic knowledge of the subject at hand. For example, rewriting medical texts in different languages would require working knowledge of what various medical and scientific terms mean.
Pharmaceutical and medical translations as well as industrial and procedural translations are not something that generic translation agencies or independent translators can undertake, purely because of the specific vocabulary and style of writing that is required.
