Latest / Stock Picking with Fexingo: Individual Equities, Research, and Building a Concentrated Portfolio / Why Your Stock Picks Drift Off Track
Transcript
- Lucas: I have been staring at my own portfolio tracker all morning, and the problem is not what I bought, but what I refuse to sell. We talk a lot about picking the right winner, but we rarely talk about the discipline required to admit when a thesis breaks. That refusal to let go is usually what destroys returns over time. Luna: It is the sunk cost fallacy wearing a financial disguise. You remember buying it because of a specific catalyst, so you keep waiting for that catalyst to return even when the underlying logic has vanished. Lucas: Exactly. And today’s market data makes this painfully obvious. Look at the divergence this week. Tesla is up nearly nine percent in five days, while Alphabet has just crashed more than eleven percent. Most retail investors are watching those green and red numbers and feeling something completely different than the reality of their actual positions. Luna: Yeah, I will definitely check that out. It helps to support independent research like this without getting bombarded by ads. Lucas: So back to the drift. When you hold a concentrated portfolio, every single name matters twice as much. If you are overweight in a stock that was once your best idea but is now failing its key metrics, you are essentially betting against yourself. The market does not care how much you paid; it only cares about future cash flows. Luna: Right, and the pain of selling is real. People hate realizing they made a mistake, so they convince themselves the dip is temporary. But holding a broken thesis just to avoid admitting error is a terrible way to compound wealth. Lucas: Let’s look at that Alphabet drop. Eleven percent in a week is not a random fluctuation; it is the market repricing a narrative. If your original reason for buying Google was based on advertising resilience, and that resilience is clearly eroding due to regulatory pressures or AI displacement, then the stock price is actually giving you the correct signal. Luna: Most people see an eleven percent drop and think, 'That’s a discount.' They do not think, 'My reason for owning this is no longer valid.' Lucas: They think it is a discount until they hold it for another year and it drops another twenty percent. The danger of individual stock picking is that you anchor to your entry price. You tell yourself, 'I’ll wait until I am back to break-even before I sell.' That is exactly how small positions become large losses. Luna: So what is the alternative? Do you just sell everything immediately when things look fuzzy? Lucas: No, you audit based on the original thesis. Write down why you bought the stock three years ago. Was it margin expansion? Was it market share growth? Then ask if those specific drivers are still intact. If the driver is gone, the stock should be sold regardless of whether you are up or down from your purchase price. Luna: That sounds incredibly disciplined, but also emotionally exhausting. How do you stop yourself from rationalizing the bad news? Lucas: You remove the emotion by focusing on opportunity cost. Every dollar trapped in a declining stock is a dollar not deployed into a compounding machine that actually works. In a concentrated portfolio, capital efficiency is everything. You cannot afford dead weight. Luna: I guess that is why Berkshire Hathaway is so effective. They treat capital as a resource to be allocated, not as personal achievements to be defended. Lucas: Precisely. Buffett and Munger never cared about their average cost basis. They only cared about where the next dollar would earn the highest risk-adjusted return. If a company stops earning high returns on capital, they sell it. Period. Luna: But individual investors often lack that kind of objective distance. We get attached to the story. We follow the CEO on social media. We read every earnings call transcript. Lucas: That engagement creates bias. The more you know about a company, the harder it is to judge it objectively. This is why many successful fund managers use a strict sell discipline. If a stock falls below a certain fundamental threshold, it gets flagged for review automatically, removing the human element of hesitation. Luna: So you suggest setting mechanical rules for selling? Like, if earnings per share declines for two quarters in a row, you review it? Lucas: Mechanical rules help, but they need to be tied to the thesis, not just technical patterns. For example, if you bought a growth stock because revenue was accelerating, and then revenue decelerates, that is a fundamental breach. You do not need to sell instantly, but you must aggressively reduce the position size until you can justify adding back. Luna: That is much smarter than just panic selling. It forces you to prove the thesis is back before you commit more capital. Lucas: Yes. And this brings us back to Tesla. Up nearly nine percent this week might feel great, but if the core margin thesis is cracking, that rally is likely noise. Many investors are chasing that green candle without checking if the long-term profitability trend is still there. Luna: Because short-term momentum can mask long-term structural decay. A stock can go up on speculation while the business fundamentals rot underneath. Lucas: Exactly. So the exercise for any listener with a concentrated portfolio is simple. Take your top three holdings. Write down the single most important reason you own each one. Now, ask yourself: is that reason still true today? Luna: If the answer is no, what do you do? Do you sell all of it at once? Lucas: You sell half. Then you wait. If the remaining half holds up or improves, you add back. If it continues to deteriorate, you sell the rest. This gradual approach reduces regret and gives the market a chance to confirm the trend. Luna: It feels counterintuitive to sell into a rally, but if the thesis is broken, the price is irrelevant. You are freeing up capital for better opportunities. Lucas: Right. And that is the ultimate goal of stock picking. Not to be right about every trade, but to ensure your capital is always working as hard as possible. Drift happens when we stop doing that work. Luna: So maybe the real alpha is not in the pick, but in the pruning. Lucas: Absolutely. Pruning is how you keep the garden alive. Without it, the weeds choke out the flowers, no matter how good the seeds were. Luna: I wonder how many listeners are sitting on positions they refuse to sell simply because they are nervous about locking in a loss. Lucas: Probably most of them. But the ones who take that audit seriously will find their portfolios becoming sharper, leaner, and much more responsive to real opportunities. Luna: It is a tough pill to swallow, but necessary. Breaking up with a bad investment is just as important as dating a good one. Lucas: Well said. So the question for this week is not what you are buying, but what you are willing to let go of. What is the one position in your book you have been avoiding selling? Luna: That is a haunting question. I hope people sleep well after answering it. Lucas: They might not tonight, but they will certainly sleep better tomorrow when the capital is freed up. Luna: Here is hoping. Thanks for keeping us grounded in the fundamentals. Lucas: Always. Next week, we dig into how to value those free-up assets.