One gender is driven by testosterone, the other by estrogens.

And the reason is because we each have a different role so that we can raise families and take care of our offspring.

If men weren't driven by those hormones, they wouldn't work dangerous jobs to provide for their families.

Women are driven by estrogens to protect the home and the offspring and to take care of the things of the family.

The differences complement, define and complete each other.