Nah women definitely don't know what they want. As a man, it's more important to understand that fact than to understand the why.
Females are weird. They're not like us. Instead of trying to figure out why they do something, just understand what they're going to do. You'll lose your mind before you figure out the why. I don't even think they know why and it's their logic.
Just know their next move and act accordingly. It's probably going to be a dumb and irrational move so why try to make sense of it? Just know what it is and you'll always have the upper hand.