Self-made and self-sufficient people live in a fantasy world, empty of the reality of God. In contrast, the poor in spirit are deeply aware of being God-made and God-sufficient:
Matthew 5:10, Philippians 2:8-9, Luke 6:20, 2 Corinthians 12:9, Psalm 37:11, James 4:10
The Sermon on the Mount is, spiritually speaking, actually the sermon from the valley. It starts low. It starts with those who feel very unlike mountains!
The celebration of Advent is possible only to those who are troubled in soul, who know themselves to be poor and imperfect, and who look forward to something greater to come.