Sector Rotation: Between Facts and Marketing Promises

In the financial world, we often hear that professionals don't pick individual stocks but rather "read" industries and move capital to where trends are strongest. Sector rotation is a real phenomenon, but there are significant differences between theory and practice that marketing materials often omit.

📈 What Sector Rotation Even Is Sector rotation is based on the observation that different industries do not grow simultaneously. The return of an individual stock largely depends on the industry to which it belongs. When capital flows into a particular sector (e.g., technology or energy), even lower-quality companies in that sector are likely to grow, while excellent companies in stagnant industries may lag.

💡 Three Steps and Their Limitations Marketing presentations often simplify the method into three easy steps: 1. Identify the capital flow: The problem is that examples in hindsight are always obvious, but predicting in advance is fraught with error. 2. Buy the entire industry via an ETF: This is a sensible step, as it eliminates the risk of an individual company, but the risk of choosing the wrong sector remains. 3. Exit in a timely manner: Discipline is crucial, but exit signals are rarely as clear as theories promise.

⚠️ Slippery Slope: A Tool, Not a Prophecy The popular rule for using moving averages (e.g., 50-day for entry and 150-day for exit) can prevent catastrophic losses in deep bear trends. However, it comes at a cost: - Lagging: Moving averages, by definition, lag behind the price; entries are always above the bottom and exits below the top. - False signals: During periods when the market moves sideways, the rule generates a series of consecutive losses due to commissions and taxes.

🧭 Diversification as the Only True Protection The most useful part of the method is risk management. The math is clear: the more uncorrelated positions you have, the less an individual mistake impacts the overall portfolio. It is crucial that the positions are actually uncorrelated – having five different tech stocks doesn't mean true diversification, as they will likely all fall simultaneously if the sector declines.

> Diversification is not a backlog to be fixed, but a deliberate decision not to bet everything on one correct forecast.

📈 How to Implement the Strategy in Practice Industry cycles are real, but they repeat with exceptions and reversals. The strategy is best used as a framework for understanding portfolio exposure, not as a tool for quick profits. Instead of looking for shortcuts, focus on: - Diversification across industries that do not move in sync. - Predetermined rules for managing losses. - Finding a sustainable framework that is not based on the belief that you know the future.