Due to the international financial storms raging at the time, the countries that had pegged their currencies to the Deutsche Mark (DM) within the European Monetary System (EMS) had to periodically decide either to maintain an independent monetary policy and devalue, or to maintain parity with the DM and lose any sovereignty over their monetary policy.
Given the frequency with which policymakers had to make these decisions, some countries lost 2 / 10  BIS central bankers' speeches  both the benefits of exchange-rate stability and their monetary policy independence. The social costs were high.