The decision to sell a winning stock should have a higher bar than the decision to buy. High-quality compounders often grow into their valuations or surprise to the upside. Selling a great business like Google, even when it appears optimistically valued, can be a mistake that forfeits future gains.
The investment thesis against Dell was its low-margin data center contracts would not be rewarded. However, during the AI boom, investors prioritized massive revenue scale and backlog growth, pushing the stock's multiple far above historical averages despite declining gross margins. Narrative trumped fundamentals.
In one year, Google went from being perceived as a laggard in the AI race, with its stock pressured, to a leader with its Gemini model. This rapid sentiment shift on a trillion-dollar company highlights the market's susceptibility to short-term narratives over long-term fundamentals.
The strategy for managing winning positions should adapt to the company's maturity. While holding a diversified behemoth like Alphabet through rich valuations is wise, taking profits on a more volatile, less-proven business like Reddit after a rapid 140% run-up is a prudent risk management tactic.
While Reddit's pseudonymous user base means it has less personal data than platforms like Facebook, it doesn't hinder monetization. Users self-select into highly specific communities (e.g., a DIY subreddit), providing strong contextual signals that allow Reddit to serve relevant ads effectively.
Financial models are inherently limited because they reflect varying degrees of the status quo. They struggle to predict both unexpected headwinds that crush value and positive black swans, like a 180-degree shift in market sentiment or explosive growth, which can make a stock appear overvalued right before a massive run-up.
To compete in AI, tech behemoths like Google are spending hundreds of billions annually on CapEx for data centers. This transforms them from asset-light software businesses into capital-intensive companies, impacting free cash flow and financial structure, a fundamental business model shift investors must recognize.
Clayton Christensen's "Innovator's Dilemma" suggests incumbents get disrupted by ignoring the low end. TSMC avoids this. While pursuing cutting-edge nodes, it continues producing older nodes on fully-depreciated fabs, which are highly profitable, leaving no undefended ground for a disruptor to enter the market.
Amazon is uniquely positioned in the AI race. Success massively benefits AWS and its chip business. However, if the AI boom fizzles, Amazon can simply reduce its massive CapEx spend and revert to its core, highly profitable businesses, creating an asymmetric risk-reward profile compared to pure-play AI companies.
Companies focused on growth, like Remitly, can appear unprofitable but possess significant latent earnings power. When market sentiment shifts, management can choose to demonstrate this by rapidly improving margins, revealing the business's true profitability potential to investors.
A key investing principle is that high-quality businesses consistently find new avenues for growth and efficiency, leading to positive surprises that valuation models miss. Conversely, mediocre businesses are prone to unexpected setbacks. This simple heuristic can be a powerful guide for long-term stock selection.