in pre industrial days, it took a dozen spinners to keep 1 weaver employed. and other yarn was spun for mending, and knitting..

spinning is not so demanding that it can't be done as a simple household chore, and young girls could spin, and so earn a small dowery for them selves.. but once they had families, it was hard to find the time to spin...
only unmarried women continued to spin past the age of 20 or so.. so many woman were spinsters till they married, and most married by age 20 or so.

spinning was one of the few occupations a woman could engage in, and still keep her reputation.