God became mad because people were rotten through and through. “The LORD saw how great man’s wickedness on the earth had become, and that every inclination of the thoughts of his heart was only evil all the time. The LORD was grieved that he had made man on the earth, and his heart was filled with pain. So the LORD said, ‘ I will wipe mankind, whom I have created from the face of the earth—men and animals and creatures that move along the ground, and birds of the air—for I am grieved that I have made them.’” (NIV, Genesis 6:5–7)