A single market like the European market, where there is intensive trade between countries, benefits from the absence of exchange rates. The success of the single market is therefore built on the bedrock of the euro. But we have seen that a single currency also brings disadvantages. Certainly for a group of countries that differ quite a bit from each other economically.
Until now the euro has not lived up to its promise of bringing sustainable economic convergence. In fact, we have seen the opposite. As devaluations are no longer possible, countries with lagging productivity growth can only restore competitiveness through wage moderation. But even in competitive countries like Germany and the Netherlands, wage growth is already muted.