What phenomena in the economic life of Spain influenced the decline of its power?

At first glance, the Spanish Empire had reached such a power that eternal prosperity could be ensured. But the country made a huge mistake in developing new lands. Colonizing almost all of South America and Mexico, Spain found tons of precious metals. But the export of this wealth to Europe led to a rapid drop in the price of gold and an increase in the prices of consumer goods. The price of bread has increased tenfold. The ineptitude of the Spanish monarchs to regulate the economy and led to the fall of the greatness of Spain.