Or, it could simply mean they did the best they could, and they are 100% accurate. The way I understand it, Hebrew does not translate exactly into Greek, the same way Greek does not translate exactly into English.
Either translation requires the inspiration and oversight of the Spirit.
I don't believe that God carved the Word in stone, and any change in a written word is anathema... I completely believe in the accuracy of the Bible, even if some words are different. The meaning is still there, and 100% accurate.