Compared to male servants, female servants were in an absolutely disadvantaged position in this employment relationship.
In Britain's traditional view, women, especially unmarried young women, were considered to have minds similar to children, and therefore absolutely incapable of full agency.
Employers were not only their employers but also their guardians, and thus enjoyed authority over their lives.
Such great power naturally brought many problems, such as various economic or physical punishments by employers against maids, or those often occurring plotlines from the single-volume novels in Eld's bookcase.
Miss Megan and Miss Catherine, as mentioned by Becky Sharp, who turned to the sex trade, were mostly former maids who were dismissed after improper relations with their employers were discovered.
Once maids acquired such a reputation in the industry, it became quite unlikely for them to find work again.