We do know God was personally regretful and disappointed in what he had done.
tis a bit strange God would be effected in such way if all was going to divine plan.
Genesis 6: (KJV)
5 And God saw that the wickedness of man was great in the earth, and that every imagination of the thoughts of his heart was only evil continually. 6 And it repented the Lord that he had made man on the earth, and it grieved him at his heart.
-Bulletproof and Waterproof don't mean Idiotproof.