When we ask God for His Kingdom to come, we are "asking God to manifest the power and glory of His kingdom in us, and throughout the world". We are asking for God's will to be done here on earth so our prayers will be "in tune and guided by God's Will".
When we pray according to God's Will we are no longer praying for ourselves, we are praying that whatever God wants, it will happen. We will stop praying only when we need something and start praying when we want God's Will to happen in the world and in our lives and in others. We will no longer be selfish, but be focusing on God and others.