There is some other country which economic condition is very poor internally some huge rich monster holding 80% of treasury in those countries but others people are very poor but this country showing Avg income normal. But actually they are not
Countries like that are most from underdeveloped countries and the people that hold such amount of percentage of the country's wealth are people in government, their families and friends because they are corrupt and give all the country's treasury to them and care less about the large population of the people. Development can't come in countries like that.
Corruption is one of many problems countries face. Ukraine was very poor when it was drained by Russia and the government members all owned villas with gold plated door knobs and drove bentleys.
When the government changed and cut some of its ties with Russia the economic conditions improved.
Some other countries lack education and are plagued by unemployment and crime like many African countries (Zimbabwe, Uganda, Somalia). It's hard to have anything developed when half of your population lives in huts and spend days drinking and getting high.