Its always corruption. Everywhere that's not doing well isn't doing well due to corruption. Corruption is the most important thing to fight and keep in check.
There's actually an inverse correlation between corruption and GDP, and a few studies showing that lowering of corruption directly boosted economic prosperity.
I wish more people actively brought up corruption, literally the most fundamental thing to fight.
Funny thing about corruption...It's very hard to quantify and as someone who spent couple of years living in China I would say there is no link between corruption and economic growth.
I would say that the difference is that China's elites are interested in China's economic growth.
They want to see China big and powerful and for that they need to sacrifice some of that greed (and really beyond certain amount of money it's about power and prestige not about endless $$$ on your bank account).
The corrupted politicians and people are only interested in enriching themselves at the expense of everything else. For them being a client state of either Russia or the EU makes no difference because they know that to reverse the course of the country it takes more than one generation and nobody has time for that especially when you are buying your next super yacht.