Don't confuse the metrics with the thing itself. The economy is not metrics in the human mind. The economy is me liking Envy apples more than disgusting Red Delicious apples and buying Envy instead. The economy is an employee getting a good offer to fill a need a company has and going back to their current employer to find out who will pay them more / gets more value from them and it's willing to thus pay more. Things like the GDP just try to approximate the sum of all these actions and exchanges.