Exchange rate risk: The main disadvantage of flexible exchange rates is their volatility. In the post–Bretton Woods era, one of the characteristics of flexible exchange rate is their excess volatility. The changes in exchange rates are more frequent and larger than the underlying fundamentals imply.
Potential for too much use of expansionary monetary policy: The downside of being able to conduct autonomous monetary policies is the ability to create higher inflation rates. Under a flexible exchange rate regime, expansionary or contractionary monetary policies can address recessionary or inflationary pressures, respectively. Especially when expansionary monetary policies are frequently used, higher rates of inflation follow.
Questionable stabilizing effects: Previously, automatic stabilizing was mentioned as an advantage of the flexible exchange rate system. Exchange rates change in the appropriate direction when the country’s inflation rate, output, and current account balance change. Especially in terms of current account imbalances, exchange rates determined in the foreign exchange markets are supposed to change to prevent the occurrence of persistent and large current account deficits and surpluses.
However, some countries have deficits (such as the U.S., Spain, Portugal, and Greece), and some countries have a surplus (such as Germany and China). Moreover, the data indicate long swings in major exchange rates, which are called misalignments.
Therefore, it seems that flexible exchange rates do not change frequently enough to eliminate current account imbalances. An adverse effect of these misalignments is that they give deficit countries the motivation to impose trade restrictions.