Alma 4:10

And thus ended the eighth year of the reign of the Judges; and the wickedness of the church was a great stumbling block to those who did not belong to the church; and thus the church began to fail in its progress.

That is how the eighth year ended. The wrong things happening in the church made it hard for people outside the church to want to join. The church stopped growing.

That ended the eighth year of the judges’ rule. The wickedness in the church became a major obstacle for those who weren’t believers, and the church’s growth stalled.