An investor's reflection published yesterday traces how a 33 percent gain on Advanced Micro Devices in 2004 cemented a habit of early profit-taking that left roughly $5,000 on the table, while a hypothetical $300 monthly investment in the SPDR S&P 500 exchange-traded fund starting in 2005 would have grown to about $300,000 by September 10, 2026.
The AMD trade that taught the wrong lesson
In 2004 the author bought 10 shares of AMD at $15 each, sold six months later at $20 for a 33 percent gain, and treated the outcome as validation of a trading instinct. The same stake held through September 10, 2026 would have been worth $5,000, a figure that assumes no additional purchases and accounts for a decade when the stock traded below the entry price.
Fake diversification and recreational chainsaw juggling
The essay describes a subsequent phase in which diversification was interpreted as owning one bank, one carmaker, and one oil company without understanding any of the three businesses. Options and short-selling are compared to recreational chainsaw juggling before learning to juggle tennis balls, though the author notes the capital at risk in those experiments was small.
The winners that actually made sense
Three long-term holdings, Alphabet, Netflix, and Intuitive Surgical, are identified as the positions that more than offset the losses. Each is up 1,000 percent or more and remains in the portfolio. The author cites fundamental reasoning: Google's durability when WebCrawler and AltaVista were still competitors, Netflix building distribution while Blockbuster defended real estate, and Intuitive Surgical's robots delivering better patient outcomes than handheld scalpels.
The index fund that did the heavy lifting
The essay's concluding math shows that $300 per month directed into SPY from 2005 through September 10, 2026 would have turned $75,600 of contributions into roughly $300,000, with about $220,000 of that total coming from returns. The fund has been available since 1993, required no stock research, and demanded only continued investment through 2008 and the COVID-19 lockdowns when doing so looked like a mistake.