Corruption is prevalent in almost every country in the world– but some are more corrupt than others. This is a complete list of the most corrupt countries in the world, ranked in order of how corrupt the country's government is. Many countries have made it to this list, thanks to its corrupt politicians with illegal money making skills. In these countries of the world, bribery and corruption are rampant. Somalia is ranked the top most corrupt country.You can sort this list of corrupt countries of the world by any column to get the most corrupt countries or least corrupt countries.
so....
https://en.wikipedia.org/wiki/Corruption_Perceptions_Index - Almost all
You need to draw the line somewhere. If 1 out of 10,000 government employees in a particular country is corrupt, are you going to label that country as a corrupt nation? I don't think so. If 10% or 20% of the employees do that, then you can label that country, but anything less than 1% is tolerable, in my opinion.
less than 1%? You must be Joke!
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In short, because at a certain point power moves you from a negative feedback loop to a positive one.
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Humans are social animals. We survive very badly as individuals or family groups, quite well as villages or tribes, and even better as cities or small nations. To operate as an effective society, you have to be nice to each other, it can’t be relentless competition and thinly veiled distrust.
But, at the same time, humans are naturally competitive. Each one wants to be more powerful than the others. Why? Who knows, possibly there’s an evolutionary advantage, possibly not, that’s another question.
Luckily these two desires work against each other. Every 5 year old finds out that demanding everyone plays their game soon means they get ignored and no-one plays with them. Things that give you influence in a society also have a high risk of making you disliked, causing that influence to wane. Our desire to be part of a society limits our desire to control that society. But, at a certain point that stops.
Once you have a sufficient amount of power (be it wealth, political power, whatever), you can actually afford to have large numbers of people dislike you, in return for having small numbers of other powerful people like you - or at least tolerate you for their own ends. Once you get caught in this positive feedback loop, maintaining power (rather than being liked) becomes a pyramid scheme. Corruption is the breaking of social contracts - i.e. being not nice. Legality isn’t the point here. Whether you are bribing someone or just shouting at them, you’re being not nice, and you’re getting away with it because of your power.
Eventually, the powerful become entirely separated from their old society, and now exist in a new, smaller society of people like them, who are also corrupt, thus establishing it as an acceptable behaviour, and the cycle continues.
This is why many societies have forced limits on the accumulation of power. Limits on terms in political office. Anti-monopoly laws. Taxes that penalise the accumulation of very large amounts of wealth. These work to brake the positive feedback (or snowball effect) of power.