Battle doesn't need a purpose; the battle is its own purpose. You don't ask why a plague spreads or a field burns. Don't ask why I fight.
- Black Knight
Old saying. Verbiage may not precisely align with Aikido, but the point remains relevant. Aikido is its own purpose.
...yeah, but if you just do stuff, and then say 'Don't ask why', then you can do whatever you want/you act without reason.
There must be a reason why you do aikido, rather than go for a walk, do karate, go go-karting, go for a nice long drive, etc. - we don't do things arbitrarily.