Why don't Christian women cover their hair when praying?

In the United States up until a very few years ago most women did cover the heads in public places, church included, and men uncovered theirs indoors, church included. Most persons wore hats when out of doors. Hats and head coverings of all sorts went out of fashion and fewer folks used them. Catholics persisted in requiring a head covering for women and even in some cases providing a common supply of minimally acceptable items at the door for the use of the faithful forgetful or the non catholic visitors who were unaware of the requirement. Some Catholic woman still continue the practice out of habit, antique piety, or cultural conformity. Habited orders of Catholic nuns continue the practice. One still sees alot of millinery in African American Protestant churches as well. So to sum it up, Some Christian woman have in the past and now still continue to wear head coverings at worship, some have shaved heads. The question is erroneous