Why did God let Jesus be born in a stable and laid in a manger?

God wanted us to always remember that Jesus came into this world with nothing. The stable and manger are a reminder of Christ's humbleness. If Jesus had been born in a palace the shepherds and common people would not have had access to him. In a manger, all mankind have access to Jesus and the word of God. The stable where Jesus was born was used for newborn sacrificial lambs, and Jesus was the Lamb of God.