Given the fact that consequences of a systemic financial crisis can be quite substantial, the optimal monetary policy might at times chose to err on the side of caution, in order to reduce the probability for a crisis to a very small 11 likelihood .
Due to the asymmetries (very low probability of very large loss) involved, actual inflation is then likely to exceed expected inflation - and optimally so - for quite some time. The above argumentation can be used to illustrate why the ECB has always stressed that its stability-oriented monetary policy strategy is more than simple inflation forecast targeting, and it is also more robust.