If you are threatened by a bear at close range, it is not likely you will stop to test the wind direction. If you shoot into a wind that is blowing back at you, the spray can end up on you. It does not take much to cause problems.

I do not think it is only women who need practice. There is limited amount of spray and there are specific techniques to use it most effectively. I think it is quite normal to freak out if a bear were attacking. Some people freeze for a few seconds. Practice breaks the "freeze" so that your action is instinctive. Very similar to stoppping yourself with an ice axe on steep snow. Just having an ice axe in hand does little good. You need to have practiced enough so that the technique is flawless and instinctive. Same with a gun. Just carrying a gun is useless unless you are trained and practice.