欧洲央行前首席经济学家奥特马尔·伊辛格（Otmar Issing）一贯指出，在没有主权的情况下，向更高层面转移职能 — — 包括货币政策 — — 的过程将造成巨大的合法性赤字。
As Otmar Issing, a former ECB chief economist, never tires of pointing out, without a sovereign, the process of transferring competences – including monetary policy – to ever higher levels will create a huge legitimacy deficit.