I did not know that Venezuela was perceived as being so corrupt. I certainly would not have ever thought it to be perceived lower than many african countries. Is it really that much crazier there then other south/central american countries?
Well... yes. I mean don't you really know that Chavez has been stealing businesses and companies and giving them to accomplices? The Chavez "nomenklatura" has taken hold of the country and been pillaging it for quite some time. The crime rate is exploding, there have been shortages of food and energy. It is a collapsing country.
At the low end, I'd guess it's probably more about measurement techniques than reality. Venezuela is not the most stable, prosperous, or wealthy society, but it's also not "hyperinflation and broad property seizure", and it's certainly not "armed gangs wandering the country raping and murdering indiscriminately."