Final answer:
Labor reformers like Sarah G. Bagley and Mary Harris "Mother" Jones were effective in improving labor conditions through advocacy, the establishment of labor unions, and influencing governmental policies, leading to significant labor reforms and laying the groundwork for future advancements.
Step-by-step explanation:
Reformers such as Sarah G. Bagley were effective in improving labor conditions during the 19th and early 20th centuries. Bagley and others brought attention to the plight of workers, particularly women and children, and advocated for better conditions, labor unions, and governmental intervention. Labor activists like Mary Harris "Mother" Jones and Florence Kelley played significant roles in this movement.
Jones's advocacy for miners earned her respect among workers and fear from industrialists, while Kelley's work led to reforms in child labor laws and the establishment of the Children's Bureau. The Progressive movement, often championed by middle-class women and men, sought to reform rather than replace capitalism and called for government regulation to ensure economic stability and fair treatment for workers. Their efforts laid the groundwork for future labor rights advancements, despite setbacks like the Lochner decision which initially undermined these efforts.