Over the last decade, the Federal Reserve, and Central Banks globally, have engaged in never-ending "emergency measures" to support asset markets. While the stated goal was that such actions were to foster full employment and price stability, there has been little evidence of success.
The chart below shows the expansion of the Fed's balance sheet and its effective "return on investment" on various aspects of the economy. No matter how you analyze it, the "effective ROI" has been lousy.
These are the unseen consequences of the Fed's monetary policies.
The only reason Central Bank liquidity "seems" to be a success is when viewed through the lens of the stock market. Through the end of the Q1-2020, using quarterly data, the stock market has returned almost 127.79% from the 2007 peak. Such is more than 3x the growth in GDP and 6.5x the increase in corporate revenue. (I have used SALES growth in the chart below as it is what happens at the top line of income statements and is not AS subject to manipulation.)