Cautionary8 min read

When Billionaires Bet Wrong: The Biggest Investment Mistakes of the Ultra-Wealthy

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Even Geniuses Get It Wrong

The ultra-wealthy are presumed to have superior investment judgment. And yet, even billionaires make catastrophic investment mistakes—sometimes losing billions on single bets.

Bill Ackman's Valeant Disaster

The Bet: In 2015, Bill Ackman built a $4 billion position in Valeant Pharmaceuticals, calling it his "highest conviction" investment.

What Went Wrong: Valeant's business model depended on acquiring drugs and dramatically raising prices—attracting regulatory scrutiny. Accounting irregularities emerged. The stock collapsed from $260 to under $15.

The Loss: Approximately $4 billion—nearly the entire position.

The Lesson: "Platform companies" that depend on financial engineering rather than product innovation are fragile.

Carl Icahn's Hertz Bet

The Bet: Carl Icahn accumulated nearly 40% of Hertz shares.

What Went Wrong: COVID-19 devastated travel. Hertz filed for bankruptcy in May 2020.

The Loss: Over $1.5 billion.

The Lesson: Even deep-value investors can be wrong. Unexpected external events can destroy any thesis.

Masayoshi Son's WeWork Catastrophe

The Bet: SoftBank invested over $10 billion in WeWork at valuations reaching $47 billion.

What Went Wrong: WeWork was actually a real estate company with massive losses. The IPO was pulled, and WeWork's valuation collapsed.

The Loss: Billions in write-downs. WeWork eventually filed for bankruptcy in 2023.

The Lesson: Valuation discipline matters. Calling a real estate company a "tech company" doesn't make it one.

Common Threads in Billionaire Mistakes

  1. Overconfidence from Past Success: Success breeds the confidence that leads to disaster
  2. Concentration: Large positions amplify both gains and losses
  3. Narrative Over Numbers: Stories justified unjustifiable valuations
  4. Ignoring Red Flags: The thesis overshadowed the risks

The Chronos Score Perspective

Billionaire investment mistakes demonstrate that Chronos Score is not guaranteed to increase. A billion-dollar loss at any age reduces future compounding potential.

The optimal Chronos Score strategy includes not just maximizing gains but avoiding catastrophic losses. A 50% loss requires a 100% gain to recover.


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