Occasionally they make historically bad bets and blow up their fortunes, and it gets eaten up it all the smaller sharks circling behind them. It used to be most billionaires only lasted (as billionaires) for 3-7 years before collapsing.
The current stock market insane binge has changed that a bit.
Yeah, they historically don't like to keep increasing their wealth, Elon musk going from 350bn to nearly 800bn in like 2 years is definitely not an example of that.
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