Prophets' Missions and Muhammad's Spread of Islam

Prophets were sent to specific nations with their mission, not to all of humanity. Ibrahim was concerned for all nations but not sent to all. Contrary to that, Muhammad's mission started in his region and expanded beyond, even during his lifetime, spreading Islam outside the Arabian desert. This indicates a broader plan by Allah, as mentioned in the Quran. This context leads to a discussion on the concept of an Ummi-in.