What is the reason behind the fact that the man pays the woman mahr (dowry) for marriage? Why does the man have to pay it but not the woman?

What is the reason behind the fact that the man pays the woman mahr (dowry) for marriage? Why does the man have to pay it but not the woman?

Dear Brother / Sister,

There has been a division of tasks between the woman and the man since ancient times so that the tasks about the dwelling and family will be fulfilled in the best way. The man works outside and works very hard when necessary to earn the bread. The woman directs the house, cooks meals and looks after the children. Therefore, all of the financial responsibilities lie on the man not woman. Mahr and nafaqa (alimony) are among those responsibilities. That division of tasks is in compliance with the nature and creation of man and woman and with the divine sunnah. Since man is stronger, he is more apt to work and earn money. The following is stated in the Quran: "Men are the protectors and maintainers of women, because Allah has given the one more (strength) than the other, and because they support them from their means." (an-Nisa, 4/34).
Mahr is like a reserve fund for the woman during her marriage life. If a woman loses her husband suddenly or if they are divorced, it will be very difficult for her to stay in the house of her husband; mahr will support her until she starts a new life.

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