Humility can come in different ways

Here is a group of people who who humbled themselves and repented and began keeping the commandments because of the preaching and efforts of Alma. They seem to have humbled themselves because of the word of God.

17 Therefore, after Alma having established the church at Sidom, seeing a great check, yea, seeing that the people were checked as to the pride of their hearts, and began to humble themselves before God, and began to assemble themselves together at their sanctuaries to worship God before the altar, watching and praying continually, that they might be delivered from Satan, and from death, and from destruction—(Alma 15)

Compare with those who are compelled to be humble. Alma later explained to a different group of people:

13 And now, because ye are compelled to be humble blessed are ye; for a man sometimes, if he is compelled to be humble, seekethrepentance; and now surely, whosoever repenteth shall find mercy; and he that findeth mercy and endureth to the end the same shall be saved.
14 And now, as I said unto you, that because ye were compelled to be humble ye were blessed, do ye not suppose that they are more blessed who truly humble themselves because of the word?
15 Yea, he that truly humbleth himself, and repenteth of his sins, and endureth to the end, the same shall be blessed—yea, much more blessed than they who are compelled to be humble because of their exceeding poverty.
16 Therefore, blessed are they who humble themselves without being compelled to be humble; or rather, in other words, blessed is he that believeth in the word of God, and is baptized withoutstubbornness of heart, yea, without being brought to know the word, or even compelled to know, before they will believe (Alma 32).