Maybe Abraham should have tried one more time?

It is important to note that it is Abraham and not God who decides to conclude the discussion at 10. “Oh do not let the Lord be angry if I speak just once more.” Abraham seems aware that he might be stretching the limit of God’s grace. He is cautious and apologetic in his final request. God, however, is as neutral and determined to forgive/to endure (נסא [ns’]) the wicked city for the sake of 10 as He was for the sake of 50 at the outset of their dialogue (v. 32).—Standing in the Breach, page 43