God has always been a flip-flopper.
"I think I'll have humanity live here forever on this paradise Earth... Oops, Adam bit the fruit! Change of plans! Humanity will live short lives now, then go to Hell or come up here to Heaven. Forever! Let's see... Gabriel, roll out a few billion guest beds..."
Same with prayer; it changes God's plans. (Unless you're a kid with untreatable cancer. "Sorry, Timmy; you die. But thanks for the pleading, frantic prayers.")
Image via Eat Liver. Source unknown. Readeth thou more