Why do you believe ban zhao would refer to herself as unworthy in the introduction?

Ban Zhao referred to herself as an unworthy writer in the introduction of her book she herself wrote. She used this negative word alongside the adjectives unsophisticated, unenlightened, and unintelligent maybe because of the way her life turned up to be since she was young. Early in her life, she was educated only at home by her mother following the Confucian doctrine that women were not equal to men and that they were incapable of school education. In addition, she got married at the age of 14 becoming the person in her husband's family with the lowest rank.  

The reason why the loss control of the Mississippi River contribute to the defeat of the Confederacy is:  Losing control of the river divided the Confederacy in two and cut off its supplies.

This make it easier for their enemies to weaken confederacy army and took them out when they have no energy or ammunition left.