Answer:
yo this is just a geuss, i have not even learned about that subject yet, but maybe it is because they did not know How to keep records. Maybe they were not smart enough to keep them. Or maybe it is because they had no access to the technology to keep records. don't fail the class because of my advise though.
Explanation:
Again don't be completly reliant on this answer, i'm literally a middle school student that has no education on this topic. i hope it helps!
