Also a pg essay from 2010: https://www.paulgraham.com/yahoo.html
>By 1998, Yahoo was the beneficiary of a de facto Ponzi scheme. Investors were excited about the Internet. One reason they were excited was Yahoo's revenue growth. So they invested in new Internet startups. The startups then used the money to buy ads on Yahoo to get traffic. Which caused yet more revenue growth for Yahoo, and further convinced investors the Internet was worth investing in. When I realized this one day, sitting in my cubicle, I jumped up like Archimedes in his bathtub, except instead of "Eureka!" I was shouting "Sell!"
That's not how Ponzi schemes work. Yahoo had a defacto _monopoly_ and the market had bad discovery leading to bad price information. There was no point at which the internet was /not/ worth investing in and everyone who had experience with it knew that.
The real problem seemed to be that you can only put so much money into pets.com before it becomes stupid. You had more short term investment capital than could be _effectively_ spent at the time. The long term players, as usual, avoided the Archimedian idealism, and were heavily rewarded anyways.
pg has startup brains.