I think things are determined by the rewards and punishments set up in systems around them.
If there is gain for a bad thing, you will get more of it.
If there is punishment for a bad thing, you will get less of it.
There are laws against corruption. But amount of corruption depends on how much money or power it can provide vs. the risk and magnitude of punishment.
Our government controls the flow of $trillions each and every year. It has the power to force taxation, print money (counting the Fed as part of government, although it technically isn't exactly), and determine where all of it goes. Even little slivers of that gravy stream can be enormous wealth to individuals.
The rewards for corruption today are enormous -- as they became during the decline of the Roman Empire. The punishments might not be a large enough deterrent.
Do people ever wonder how higher-level politicians work their entire careers in politics, get paid maybe $100k-$200k/year for a decade or two, yet exit politics with a net worth of $20 million or $100 million? There are many well-known grifts. It's not technically bribery because no company tells you what to do. But generally politicians know what particular companies want. And if the company has long established a policy of hiring helpful former politicians into lucrative directorships or consultancies, or paying enormous speaking fees, or arranging lucrative book deals, politicians can be helpful and then get rewarded without anyone ever having said "if you do this, I will will pay you that." There is the real-estate grift. Where you know a freeway will be put in, or some land purchased for a government housing project, etc., and your pal the real-estate developer happens to buy the land ahead of time, then make huge money on it. And you happened to be part owner. Or the guy gives you a sweet deal on a multimillion-dollar home or several later. There is the trading grift. You know that some legislation is going to pass that affects this or that company, or bond prices, or whatever. You buy or sell beforehand. This insider trading is highly illegal for you and me. But it is legal for congressmen and women.
I wish government organizations were pure and good. But I know that humans are humans -- always -- and it boils down to what the rewards and penalties are. It will always be a fight against corruption, just like it is a fight against rust and decay to keep things working. You need routine examination, cleaning, maintenance, and cutting out rot and replacing that part.