The Watch Tower Society introduced the New World Translation of the New Testament in 1950, and of the Old Testament in 1960. The reason given for the translation and switching to it was that the English in the KJV is too old. The names of the translators were kept a secret, and the reason given for it was to not receive glory for their translation work.
Later, a member of the Governing Body of the Watch Tower Society named Raymond Franz revealed that the "translation" had been done by five men: his uncle Frederick Franz, George Gangas, Milton Henschel, Nathan Knorr, and Albert Schroeder. Not only did none of the five men speak the Bible's original languages of Hebrew and Greek, none of them even had college degrees. Four of them had never set foot on a college campus, while the fifth had dropped out after two years.
Their ignorance of the languages they claimed to have translated isn't baffling since what they intended to do and did do was not translate them but simply change the English Bible in the place (eg. John 1:1, Colossians 1:16, Hebrews 1:8, Proverbs 1:20) that contradict the Watch Tower Society's heresies. They should have heeded God's stern warning to add nothing to and delete nothing from the Bible:
"For I testify to everyone who hears the words of the prophecy of this book: If anyone adds to these things, God will add to him the plagues that are written in this book; and if anyone takes away from the words of the book of this prophecy, God shall take away his part from the Book of Life, from the holy city, and from the things which are written in this book" (Revelation 22:18-19).