Sometimes it is fruitful to look at it from the other side -- why does a 200+ 6 foot tall ectomorphic norwegian weight liftin' male with a background in other arts take aikido?
Of course I'm talking about me here...
I enjoyed the grace and beauty of the art. I also thought "this looks like something really hard for me to learn to do well". And... Wait for it... It looked interesting and fun.
My other answer to the question of "why do you do aikido" is to point out something else... No one ever asks why I go to the gym to lift weights and work out on the ellipticals (real reason is back and knee problems, trying to prevent that early heart attack, and a chance to get out of my workshop). No one asks why I enjoy dog training. I just like dogs... No one asks why I enjoy playing tennis -- its just fun!
We all have hobbies, avocations, and we all take them to varied levels of intensity. My Aikido training is probably my most intensely focused activity for me behind my time with my family and my training in Japanese sword crafts. Unfortunately I don't have more time for more things to get enthused about.
So... All that said... I imagine there are lots of people just like me -- male and female both. They do aikido because it is what they do. No real profound reason, no pressing, critical force that insists they do it. I certainly enjoy my training. And I get antsy when I miss training. And I have the great benefit of training in the dojo 3 times a week and often spend time doing solo stuff the other days (the benefit of being self-employed, working at home, and needing to take breaks periodically -- I get to work on kengi, jogi, aikitaiso, etc.)
Sometimes I think people think too much, look too deep, and try to find reasons when in fact it is just what it is. Kinda like that great zen quote... ""Remember; no matter where you go, there you are."- B. Banzai".
Sometimes the reasons are no deeper than that...