The proliferation of billboards for highly specialized, unintelligible B2B companies along Silicon Valley's Highway 101 signals market froth. When advertising shifts from consumer brands to obscure B2B2B services, it suggests excess capital is flowing deep into the tech stack, a classic sign of a potential bubble.

During the bubble, a lack of profits was paradoxically an advantage for tech stocks. It removed traditional valuation metrics like P/E ratios that would have anchored prices to reality. This "valuation vacuum" allowed investors' imaginations and narratives to drive stock prices to speculative heights.

The primary driver of market fluctuations is the dramatic shift in attitudes toward risk. In good times, investors become risk-tolerant and chase gains ('Risk is my friend'). In bad times, risk aversion dominates ('Get me out at any price'). This emotional pendulum causes security prices to fluctuate far more than their underlying intrinsic values.

Widespread public debate about whether a market is in a bubble is evidence that it is not. A true financial bubble requires capitulation, where nearly everyone believes the high valuations are justified and the skepticism disappears. As long as there are many vocal doubters, the market has not reached the euphoric peak that precedes a crash.

Investors often invent compelling secular narratives—like a permanent housing shortage or "Zoomers don't drink"—to justify recent price movements. In reality, these stories are frequently post-hoc rationalizations for normal cyclical fluctuations. The narrative typically follows the price, not the other way around, leading to flawed trend extrapolation.

Asnes employs a strict framework before using the word "bubble." He will only apply the label after exhaustively attempting—and failing—to construct a set of assumptions, however improbable, that could justify observed market prices. This separates mere overvaluation from true speculative mania disconnected from reality.

In a late-stage bubble, investor expectations are so high that even flawless financial results, like Nvidia's record-breaking revenue, fail to boost the stock price. This disconnect signals that market sentiment is saturated and fragile, responding more to narrative than fundamentals.

The stock market is not overvalued based on historical metrics; it's a forward-looking mechanism pricing in massive future productivity gains from AI and deregulation. Investors are betting on a fundamentally more efficient economy, justifying valuations that seem detached from today's reality.

The era of constant central bank intervention has rendered traditional value investing irrelevant. Market movements are now dictated by liquidity and stimulus flows, not by fundamental analysis of a company's intrinsic value. Investors must now track the 'liquidity impulse' to succeed.