The cost of inaction can be immense. One speaker's "worst investment" wasn't a loss but passing on three startups in his direct area of expertise—Polymarket, Calshee, and Whatnot. Despite being an early user and having direct contact with the founders, he failed to invest, missing out on multi-billion dollar outcomes.

This "via negativa" approach, inspired by Sun Tzu and Charlie Munger, posits that the easiest way to improve returns is by systematically avoiding common mistakes. Instead of trying to be brilliant, investors should focus on not doing "dumb stuff," as it's easier to identify what leads to failure than what guarantees success.

Most investors cannot excel at both aggressive offense (seeking more winners) and disciplined defense (avoiding losers). These require different mindsets. To build a coherent strategy, one must make a conscious choice about which path to prioritize, as very few possess the skills to master both simultaneously.

Don't chase every deal. Like a spearfisherman, anchor in a strategic area and wait patiently for the 'big fish'—a once-in-a-decade opportunity—then act decisively. This requires years of preparation and the discipline to let smaller opportunities pass by, focusing only on transformative deals.

Post-mortems of bad investments reveal the cause is never a calculation error but always a psychological bias or emotional trap. Sequoia catalogs ~40 of these, including failing to separate the emotional 'thrill of the chase' from the clinical, objective assessment required for sound decision-making.

To avoid emotional, performance-chasing mistakes, write down your selling criteria in advance and intentionally exclude recent performance from the list. This forces a focus on more rational reasons, such as a broken investment thesis, manager changes, excessive fees, or shifting personal goals, thereby preventing reactionary decisions based on market noise.

The true cost of becoming great at one thing isn't the work, but the discipline to ignore all other 'shiny objects.' Success comes from the paths untaken. The fear of missing out (FOMO) is the price of focus.

Gardner notes that whenever he has broken his own rule and invested an "exciting amount" into a new idea, it has generally failed. This emotional excitement leads to poor decision-making and oversized bets on unproven theses. Strict discipline on initial position sizing is a crucial defense against one's own biases.

Constantly jumping to the next hot trend like crypto, cannabis, or AI is a sign of chasing an outcome (money) rather than engaging in a process. This approach fails because success requires deep interest and persistence, which trend-chasers lack.