Why is the vagina so sensitive to the elements?

This is a genuine question. Why is the vagina so much more sensitive to the outside world as opposed to something like the anus? You don’t have to worry about the pH balance or the microbiome of your butt when you’re picking out a soap at walmart in fear that you’ll get a raging infection. The anus is an organ just like the vagina, but the vagina requires so much more maintenance and care.