Satisfaction

Nothing we do is ever good enough. We always need to do more. Set a goal? Do everything to make it happen. Attain it? Set another goal and aim towards it. You're always climbing, without ever being able to reach the ceiling.

We keep setting ourselves up for success and never failure, all the while never knowing what true success really is. Comparing ourselves to others, and often failing to look within ourselves; we make the materialistic culture succeed and slave ourselves day by day to gather meaningless trinkets. Always thinking and rationalizing that, eventually, after scaling so much, everything will pay off and we will be "happy." But that's also without knowing what "happiness" truly is.

After all, we are never satisfied and thus can never be fully "happy."

That's human nature I guess.