From a pessimistic viewpoint, an abrupt change in nominal rates might make the fiscal situation severer and possibly have an effect on the financial system. Somewhat ironically, the success in overcoming deflation might produce unfavorable spillover effects, given the significant size of the government’s debts.
In an extreme case where there is a grave negative impact on financial stability, a central bank might have to choose either financial stability or price stability, no matter how strongly it is committed to price stability.