"And I, Amaleki, had a brother, who also went with them; and I have not since known concerning them. And I am about to lie down in my grave; and these plates are full. And I make an end of my speaking."
When Lehi and Nephi began to write, their sacred plates were mostly blank and full of possibility. By the time Jacob received the plates, however, they were more than half full, and so he wrote with greater concision. Enos, getting the plates after Jacob, wrote even more carefully, and Jarom more carefully still.
All the record-keepers from Jarom through Amaleki were faced with the terrible challenge of writing on plates that were nearly full. What do you say into a sacred history with almost no space left?
Only after Amaleki filled the plates and thus reopened history could the people see their own generation's experience as sacred again.