From the beginning of time, we have always had a prophet on the Earth. If we read through the Bible we can see all throughout the Old Testament that God has always given us prophets, He gave us Adam, Noah, Abraham, Isaac, Isaiah etc. God gives us prophets because He loves us. Why do you think that God gives us prophets? There could be many reasons that He gives them to us, He wants us to live with Him again prophets guide and direct us in all things that we do. If we heed to what prohpets tell us then we will be able to make it once again into the Kingdom of God.
One reason that is definite is explained in the book of Amos in the Old Testament. The prophet Amos speaks about prophets and he says this;
"Surely the Lod God will do nothing, but he revealeth his secret unto his servants the prophets." (Amos 3:7)
I know that God gives us prophets, He always has and He always will. He loves us and cares for us and wants us to return to Him.