Durable Capital's process includes a mandatory three-year look-back for every investment, comparing the original thesis to reality. This is crucial because while small deviations can be excused quarterly, compounding them over 12 quarters reveals significant thesis drift. The formal review forces an intellectually honest assessment of whether a slow-moving problem has become critical.

Compounding is a fragile process. Every portfolio adjustment, like trimming or panic selling, is like opening a door and letting heat escape. Treating your portfolio as a contained machine that works best when untouched reframes "doing nothing" as a strategic, structural advantage.

The 0-12 month market is hyper-competitive, while quantitative models lose predictive power beyond five years. The 2-5 year timeframe is ideal for value strategies like special situations and mean reversion, offering a balance of predictability and reduced competition.

The primary role of a small fixed-income allocation (e.g., 10%) isn't to generate returns but to act as a behavioral stabilizer. It provides a simple, mechanical rebalancing rule: trim equities if bonds fall to 5%, buy more if they rise to 15%. This forces disciplined "buy low, sell high" behavior.

The modern market is driven by short-term incentives, with hedge funds and pod shops trading based on quarterly estimates. This creates volatility and mispricing. An investor who can withstand short-term underperformance and maintain a multi-year view can exploit these structural inefficiencies.

Methodical Investment's David Kaiser suggests that the primary benefit of a rules-based system isn't just performance, but the psychological comfort it provides. It establishes a clear process (if X happens, do Y), removing emotional decision-making and making strategy easier to communicate, especially during volatile periods.

To combat the urge for constant activity, which often harms returns, investor Stig Brodersen intentionally reviews his portfolio's performance only once a year. This forces a long-term perspective and prevents emotional, short-sighted trading based on market fluctuations.

Jeff Gundlach reveals the optimal horizon for investment decisions is 18 to 24 months. Shorter periods are market noise, while longer five-year horizons, even with perfect foresight, often lead to being fired due to interim underperformance. This window balances strategic conviction with career viability.

Rather than passively holding a stock, the "buy and optimize" strategy involves actively managing its weighting in a portfolio. As a stock becomes more expensive relative to its intrinsic value, the position is trimmed, and when it gets cheaper, it is increased, creating an additional layer of return.