It is also possible in some countries that, even at lower interest rates, neither the demand for credit nor the willingness of banks to supply it will be increased as much as would normally be the case.
This does not mean that monetary policy in those countries has become completely ineffective – in many cases, it may simply lead policy-makers to lower overnight rates by more than usual. Nonetheless, it is handy in such circumstances to have an additional channel – namely, fiscal policy – that can affect aggregate demand if needed.