The Importance of God's Mercy

In some translations you'll have, I'm not a man that I should repent, right, or this is or change my mind. And what is interesting is that we actually do have examples and we've looked at some of them where God does have his mind changed. But what's different about it is that he changes his mind when somebody appeals to his mercy. You don't see these instances where someone's like, well, I know you were going to be merciful. Could you be wrathful instead?