Problem: interest rates are inhibiting lending and growth. Solution: create a few trillion units of currency and buy enough sovereign bonds to drop interest rates to near-zero.
Problem: nobody’s left who can afford to buy the new nosebleed-priced flats that underpin China’s miracle-grow economy. Solution: create new currency, lend it to local government agencies who then buy the empty flats.
Problem: stagnant employment and deflation. Solution: create a trillion in new currency, buy a trillion in new government bonds that then fund infrastructure projects, i.e. bridges to nowhere.