Ukraine is actually facing a lot of problems, some of them economic, but most of them are not economic in nature, but influence the economy to a great degree.
Corruption - the country has been struggling with corruption for years, and despite some efforts, a portion of the public money is still illegally appropriated by the politicians and their associates
Russia's pressure on Ukraine - ever since Ukraine started moving more towards the Western Europe, Russia either stopped giving a support that it was giving before or directly decreased the amount of money in Ukraine, for example by demanding the return of the (very high) debt that Ukraine has towards Russia
Destruction caused by war - the recent and partially ongoing war has caused a lot of losses for Ukraine, including to its infrastructure and a lack of infrastructure is bad for the economy
Lack of very good trade deals - for example, Ukraine is not in the EU so it cannot benefit from the free market, such as some of it's neighbours - Poland and Slovakia. <span />
Answer: Any 'European' country who fulfils the EU criteria of membership can apply to join the EU. Membership criteria are known as the Copenhagen criteria. These include 'a free-market economy, a stable democracy and the rule of law, and the acceptance of all EU legislation.
