Sayyiduna Amr bin Salamah (may Allah be pleased with him) says that my people came to the Prophet (peace and blessings be upon him). When they had read the Qur'an and fulfilled their needs, they asked who should lead them in prayer. He (peace and blessings be upon him) said: "The one who has memorised the most Qur'an." When they came back to their people, they asked about this, but no one had memorised more Qur'an than me. They put me forward while I was a boy, and I would lead them in prayer. Whenever there was a gathering, I was their imam.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5139