We do not know how far they understand the gravity of sin. As for the act of contrition, you are leaving out the greatest factor of all—God’s grace. In a flash God can enlighten the mind and move the will to a purely interior act of contrition of which the onlookers know nothing. And God alone knows how many are thus saved.
Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty