The translations are works of human beings so they undoubtedly contain many errors. If I were to translate a sentence from another language to English and another person were to do the same, there's a very high chance that we'd have similar but different translations. One of us may unintentionally be leading the listener/reader to unexpected conclusions. This is because the Qur'an is a holy book and is scrutinized and placed under a microscope. The same is done with every other religious book but the problem is, a lot of the times, what is under the microscope may not be the word of God - for example, the most popular version of the Bible, the King James Version, contains a lot of errors, most of which are extremely obvious. Despite there being more "accurate" translations of the Greek New Testament, the KJV is still the most famous and thus, the most scrutinized. Christians in their Bible study groups who are studying the KJV derive many of their ideas from specific verses that may have been mistranslated and reach conclusions that were never meant to be reached. This is why the Qur'an was preserved in the language it was revealed. Even the Arabic of the Qur'an is not equivalent to modern Arabic and no effort has been made to make it so because it is the literal word of Allah .