Why did the Third Caliph Uthman Burn the Copies of Quran?

Orientalists often question the historical authenticity of the Qur'an by accusing Uthman ibn Affan (ra) - The 3rd Caliph of Islam, of burning copies of the Qur'an in his reign. Shaykh Yasir Qadhi answers - The historical compilation of the Qur'an by the 3rd Caliph Uthman (ra).