The Stability and Growth Pact has largely failed on both counts. It proved toothless in good times when the need to build up sufficient fiscal buffers for bad times was ignored. And it amplified procyclicality in bad times.
From 2009 to 2018, the average cyclically adjusted government primary balance was -5.7% for Japan and -3.6% for the United States, but 0.5% for the euro area. And even when the euro area aggregate fiscal stance was considered broadly appropriate, such as in the most recent years, it was wrongly distributed across countries.