In their must read annual report, The Bank of International Settlements (aka "the central bank of central banks" points out that there is only so much that monetary policy can do and basically the central banks are "spent":
Six years ago, in mid-2007, cracks started to appear in the financial system. Little more than a year later, Lehman Brothers failed, bringing advanced economies to the verge of collapse. Throughout the ensuing half-decade of recession and slow recovery, central banks in these economies have been forced to look for ways to increase their degree of accommodation. First they lowered the policy rate to essentially zero, where it has been ever since in the United States, United Kingdom and euro area. (And where it has stood in Japan since the mid-1990s!)
Next, these central banks began expanding their balance sheets, which are now collectively at roughly three times their pre-crisis level – and rising. Originally forged as a description of central bank actions to prevent financial collapse, the phrase "whatever it takes" has become a rallying cry for central banks to continue their extraordinary actions. But we are past the height of the crisis, and the goal of policy has changed – to return still sluggish economies to strong and sustainable growth. Can central banks now really do "whatever it takes" to achieve that goal? As each day goes by, it seems less and less likely. Central banks cannot repair the balance sheets of households and financial institutions. Central banks cannot ensure the sustainability of fiscal finances. And, most of all, central banks cannot enact the structural economic and financial reforms needed to return economies to the real growth paths authorities and their publics both want and expect.
What central bank accommodation has done during the recovery is to borrow time – time for balance sheet repair, time for fiscal consolidation, and time for reforms to restore productivity growth. But the time has not been well used, as continued low interest rates and unconventional policies have made it easy for the private sector to postpone deleveraging, easy for the government to finance deficits, and easy for the authorities to delay needed reforms in the real economy and in the financial system. After all, cheap money makes it easier to borrow than to save, easier to spend than to tax, easier to remain the same than to change.
Yes, in some countries the household sector has made headway with the gruelling task of deleveraging. Some financial institutions are better capitalised. Some fiscal authorities have begun painful but essential consolidation. And yes, much of the difficult work of financial reform has been completed. But overall, progress has been slow, halting and uneven across countries. Households and firms continue to hope that if they wait, asset values and revenues will rise and their balance sheets improve. Governments hope that if they wait, the economy will grow, driving down the ratio of debt to GDP. And politicians hope that if they wait, incomes and profits will start to grow again, making the reform of labour and product markets less urgent. But waiting will not make things any easier, particularly as public support and patience erode.
Alas, central banks cannot do more without compounding the risks they have already created. Instead, they must re-emphasise their traditional focus – albeit expanded to include financial stability – and thereby encourage needed adjustments rather than retard them with near-zero interest rates and purchases of ever larger quantities of government securities. And they must urge authorities to speed up reforms in labour and product markets, reforms that will enhance productivity and encourage employment growth rather than provide the false comfort that it will be easier later.