On the positive side, there may be stronger than anticipated effects stemming from the extensive macroeconomic stimulus under way and from other policy measures taken. Confidence may also improve more quickly than currently expected.
An important impediment to the use of monetary policy to mitigate macroprudential problems is that higher interest rates could drive forecast CPI (say) inflation below some targeted or desired level. Some worry that this might lead the public to believe that the authorities were no longer interested in stabilising prices, and that this might encourage inflationary expectations over time.