You're implying that if something can be outdone it doesn't have a purpose, which seems to rule out purposes for pretty much everything.

I'm sure there's always someone that can write books or maths papers or symphonies better than you. I don't think this robs you of purpose, unless your purpose is to be the absolute best at something.

Anyway, I find it curious that you would say logic is a quintessentially human trait, because humans are naturally quite bad at logic.