are as follow:
"why is it not mandatory?"
The answer to your question is a question and it is,
is everything mandatory or somethings yes and somethings no?
"Does "culture" make it so?"
Yes because those people who belong to that culture are happy with it and worked out for them.
"does culture state otherwise?"
Their culture yes, and put in mind that this culture see something wrong if the man stays at home but searching for job is continuing, in my culture a man must work even if it is from home and nowadays some works can be done from home, this is my culture nomerci, and in my culture man must work.
"then it is the people who ,with their decision, change culture."
People are free to choose what they think it suits them and at the same time they should not blame others if the culture they choose turned negatively and affected them in a negative way then they should blame them selves for choosing this culture.
Do you agree nomerci that before making a choice a study should be done to see if this choice is good or not?
In my culture than man can tell his wife not work if the work she is doing is letting her away from him and their children and at the same time he can not force her to leave the work, so the solution here is one of two either they go to the court or she quit if she want to stay with her husband and children and again these two solutions must be studied first.
I did not understand anything in your last paragraph.