#economics

Spend enough time reading about startups and it's easy to come away with the impression that success means conquering the world.

Millions of users. Billion-dollar valuations. Products everyone has heard of.

Those stories are fascinating, but they also distort our intuition.

Imagine you build an online service that people find genuinely useful. Not revolutionary. Not something that dominates headlines. Just something that solves a real problem well enough that people are happy to pay $8 per month.

Now imagine that 10,000 people subscribe.

That's:

\[ 10,\!000 \times \$8 = \$80,\!000 \text{ per month} \]

or

\[ \$960,\!000 \text{ per year} \]

before expenses.

Those numbers aren't remarkable.

The surprising part is how few people they represent.

With a world population of roughly 8.2 billion, 10,000 customers amount to about

\[ \frac{10,\!000}{8.2\times10^9}\times100\% \approx0.00012\% \]

of humanity.

That is about one person out of every 820,000.

Think about that for a moment.

The internet often feels crowded because we can see everyone at once. Social media places millions of people in the same feed, making it seem as though our work must compete with all of them.

In reality, very few businesses are trying to serve everyone.

The most resilient ones often serve a particular group extraordinarily well.

Maybe they're musicians who need better notation software.

Maybe they're birdwatchers.

Maybe they're language learners.

For years, one of the most common pieces of investing advice has been remarkably simple: buy a broad market index fund and hold it for the long run.

There is a great deal of evidence supporting that advice. Index funds offer low costs, broad diversification, and a way to participate in the growth of the economy without attempting to outsmart the market. For many investors, they remain an excellent choice.

Still, there is a subtle detail that is easy to miss.

Many investors think of a fund tracking the S&P 500 as a basket containing five hundred companies of roughly equal importance. In reality, that is not how most major indexes work.

The largest companies receive the largest weights.

This means that although an index fund may hold hundreds of businesses, its performance can be influenced disproportionately by a much smaller group.

That distinction may not matter much during ordinary times. It becomes more interesting when a particular sector captures the imagination of investors.

In the current market, artificial intelligence has become one of the dominant narratives. Enormous amounts of capital have flowed toward companies seen as leaders or beneficiaries of the AI boom. Some of these firms have reached valuations that would have seemed extraordinary only a decade ago.

Whether this enthusiasm proves fully justified is a question for the future. The technology itself is undeniably impressive. The economic consequences may be equally profound.