The economies work in cicles, it's not that it's bad or good. Long periods of the same, inflation, desinflation or to a leasser extent desinflation. Are what cause all these issues.

So if you work in the European central bank your goal would be to stabilise these changes to small periods of time, but you don't always have control, because if the US wanted (for example), they could release enough euros that would throw our currency stability out the window.

(Of course this isn't in their interest(not even China would want this I hope) because the world economy it's too interconnected.)

So when you think your politicians have control over your economy, think again. They have a limited amount of control, along with policy it should be enough to run a country.

(Sorry I keeped going in the topic of the original comment after I answered you XD)