Re: Why do you do Aikido?
Back when I was in high school, a friend of mine and I were discussing martial arts and what we might take up to develop self-defence skills. Aikido sounded appealing as we'd heard from a friend that it used the opponent's force against them.
When I asked my practicing friend the usual "What happens if I go to punch you in the head?" his response, when I motioned as much was, to my surprise at the time, to step behind me instead of just block it. I thought that this was quite remarkable and signed up soon afterwards.
The benefits of training -- faster reactions, less walking into furniture at home and the development of uncanny coordination kept me going with it through university, along with a developing appreciation that allowed me to see the good in the bad and the bad in the good, along with a period of feeling something of an (idealistic in hindsight) "love towards all beings".
I stopped for some years after my shodan, however, due to a combination of politics, work, personal issues (I didn't want to be considered "senior" in my dojo when I felt I had a lot of issues that I needed to overcome) and moving to a different city. Starting again, as much as I might write an essay about my thoughts on practice, self defence and self-development, maybe the most honest reason is that going to training with positive people, fantastic teachers and making concrete progress over the last few months simply makes me feel great about myself.