Humanity Betrayed God

(Given free will, humans chose rebellion (or sin) against their very creator. They kept at it, too. God is love but must punish sin with death.)

"They did not keep God's covenant, but refused to walk according to his law. They forgot his works and the wonders that he had shown them."
Psalm 78:10-11

"All have turned away, they have together become worthless; there is no one who does good, not even one."
Romans 3:12

"Then the LORD saw that the wickedness of man was great upon the earth, and that every inclination of the thoughts of his heart was altogether evil all the time. And the LORD regretted that He had made man on the earth, and He was grieved in His heart. So the LORD said, 'I will blot out man, whom I have created, from the face of the earth - every man and beast and crawling creature and bird of the air - for I am grieved that I have made them.'"
Genesis 6:5-7