People like to joke about how terrible online translators such as Google Translate are, but the fact is that no matter how advanced or thorough it is, no automated translation can capture the essence of the original document the way human translators do.
The reasons for this predictable failure include language's ever-changing nature, its intrinsic connection with culture and society, and the ensuing regional differences. Accurate translation therefore necessitates human translators who understand these impediments and provide authentic translations in spite of and in light of those factors.
1. Constant Evolution
Language evolution has been a trend throughout history. However, with the rise of the internet and increasing interaction between people from all different parts of the world, universal changes in many languages are currently proceeding at record speeds. These developments render automated translation services useless for material pertaining to topics such as popular culture and current events.
2. Cultural & Social Context
Language cannot exist in a vacuum. Language only exists where people exist to use it, which implies that these people have an intrinsic influence on the language. But people vary widely based on background, culture, education, and experience, signifying that words change meaning, evoke diverse associations, or imply varied connotations based on their context. As automated translators cannot anticipate this context, their results are generic and at times completely erroneous.
3. Regional & Dialectical Differences
Not only does language vary based on time and culture, but each language also contains countless regional varieties. These differences often have widely divergent vocabularies, making it imperative to take into account the possible meanings of the words used and their effect on the finished product. While even human translators cannot fully anticipate every possible significance of every word or phrase, their knowledge will always be more current and complete than an automated translator.
No translator -- human or automated -- can always know the newest language trends, understand all of the cultural differences, or master all possible regional varieties. People who use the target language on a regular basis, however, adapt quickly and comprehensively to changes in all three of these important factors. A skill that automated translation is a long way from accomplishing.