Idk....think the point is not rly happines...but strive. I think it is in our nature, gene or spirit, whatever u want rly...to keep on pushing it. Maybe at the end it comes to as simple thing as an ego. Like trying harder/pushing further is programed in us. Think if u took the goal (in this case happines) away...we would keep on pushing forward.
Well we can't push backwards either.
Ok, that was a bad joke :D But I can see what you say.