The Core Worldview of Momentum Investing
What if the best time to buy a stock is not when it is cheap, but when it is already rising? Momentum investing is built on a counterintuitive truth: securities that have been outperforming tend to continue outperforming for months. Buying strength — not weakness — is the momentum investor's discipline.
Why This Matters
Momentum investing's intellectual roots lie in empirical research and practitioner observation, not armchair theory. Richard Driehaus, building his approach in Chicago from the 1970s, observed that stocks rising on strong earnings acceleration tended to keep rising — that the market was systematically slow to fully price in improving fundamentals. William O'Neil fused momentum with fundamental screening, codifying the CAN SLIM system in the 1960s. Mark Minervini refined it into a surgical approach to high-probability setups. The academic legitimacy came later: Jegadeesh and Titman's 1993 paper demonstrated that stocks with strong 3–12 month relative strength significantly outperformed over the subsequent 3–12 months. Momentum was real, persistent, and pervasive. It is now one of the most well-documented factors in all of finance.
Foundational Beliefs
PRICE TREND CARRIES INFORMATION
A stock rising on high volume while the market sells off is telling you something: that informed buyers — institutions, insiders, specialists — are accumulating. The price is the signal. Most investors are trained to distrust rising prices; the momentum investor is trained to follow them, because the market often knows things before the analyst does.
EARNINGS ACCELERATION IS THE FUNDAMENTAL CATALYST
The best momentum stocks are not just technically strong — they are businesses with accelerating earnings growth, improving return on equity, and expanding profit margins. Driehaus called this the "earnings surprise" phenomenon: when a company reports earnings meaningfully above estimates, the stock gaps up, institutions scramble to buy, and the price action often continues for months. The fundamental and the technical reinforce each other.
BUY STRENGTH; SELL WEAKNESS
The momentum investor buys stocks making new 52-week highs, not new 52-week lows. This is the single most counterintuitive aspect of the school — it runs directly against the instinct to buy "on the dip." The logic: a stock at a new high has overcome all prior resistance; every holder is in profit; there is no overhead supply to cap the move.
RISK MANAGEMENT IS NON-NEGOTIABLE
Where value investors accept paper losses as temporary, momentum investors cannot. A stock that fails to move as expected — or worse, reverses — is telling you the thesis is wrong. The stop-loss (typically 7–10% below the purchase price) is not a sign of weakness; it is the mechanism that preserves capital so you can play again when conditions are right. Losing small and winning big is the arithmetic foundation of the strategy.
MARKET DIRECTION DETERMINES EVERYTHING
Individual stock selection is secondary to market environment. In a strong bull market, 3 out of 4 stocks rise; in a bear market, 3 out of 4 fall. The momentum investor watches the broad market indices, institutional accumulation/distribution patterns, and leading stocks to determine whether conditions favour aggressive buying or defensive positioning. When in doubt, cash is a position.
Richard Driehaus's Perspective
“I believe that the elements of timing and price action are more important than anything else when you're dealing with the stock market.”
Richard Driehaus
“The whole secret to winning in the stock market is to lose the least amount possible when you're not right.”
William O'Neil
“There are no good or bad stocks. There are only stocks that go up and stocks that go down.”
Richard Driehaus
“You need to keep the risk of ruin at zero in order to stay in the game long enough to let the odds work in your favour.”
Mark Minervini
A Real Example
In 2003, as markets recovered from the dot-com crash, Minervini applied his SEPA methodology to identify a cluster of stocks setting up in tight, high-volume bases after deep corrections. Among them was Hansen Natural (now Monster Beverage) — a small beverage company showing accelerating revenue growth, improving margins, and a perfectly formed consolidation pattern. The stock broke out on volume in late 2003 and proceeded to gain over 500% in the following 18 months. The setup was textbook: strong fundamentals, tight price action, high relative strength, clear base breakout with volume confirmation. No fundamental analysis would have identified the timing; the price and volume told the story.
The Common Mistake
The most common mistake in Momentum Investing is holding losers. Value investors hold losers because they believe in mean reversion; momentum investors who hold losers are violating their own rules. A stock that drops 10% below your purchase price is no longer a momentum stock — it has reversed. Rationalising why it should recover ("the fundamentals are still good") is the classic transition from momentum discipline to hope-based investing. The stop-loss exists precisely to prevent this. Cut the loss and move on.
Key Takeaways
- Momentum Investing is built on the empirical fact that relative strength tends to persist.
- Earnings acceleration is the fundamental catalyst that creates the most powerful momentum moves.
- Buying strength — not weakness — is the core discipline that separates momentum from contrarianism.
- Risk management (the stop-loss) is the strategy's foundation, not an afterthought.
- Market environment dictates position size and aggression — no system works in all conditions.
- Discipline and consistency of execution matter more than any individual trade.
What to Read Next
Read: The five foundational lessons in Momentum Investing — starting with What Momentum Actually Is (Driehaus) and ending with Risk Management (Minervini). Then explore the Concept Library entries for Relative Strength, Base Formation, and Breakout.
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CAN SLIM — The Anatomy of a Market Leader