Well, one could ask the same question about Mormonism. If Mormonism came from Christianity, how'd it go from, "From everlasting to everlasting You alone are God," to, "God is a created being who, like many before Him, earned His Godlike position through righteousness"? It's a twist on the truth. Both Islam and Mormonism were founded by servants of the enemy, and unsurprisingly have many similarities. Their minimal differences are designed to allure difference groups of people into the same trap, and to cover the tracks of their common originator.