The Hidden Cost of Market Volatility: Behavioral Mistakes
By James Picerno | The Milwaukee Company
Volatility exposes investor psychology
Behavioral biases spike precisely when discipline matters most
Rules tend to beat emotions most of the time
Market volatility doesn’t just rattle markets—it rattles investors, which in turn exposes behavioral risk. When markets lurch and headlines turn chaotic, that’s when dormant biases like loss aversion, herding, and overconfidence can surge to the surface and quietly steer investors toward costly decisions.
In a previous essay, we outlined several steps for reviewing your portfolio strategy when market volatility spikes. That discussion assumed a rational, cool‑headed investor—an assumption that may be too generous at times, especially during market downturns. As a complement, let’s consider the behavioral dimension during periods of market turbulence, focusing on the key risks to be aware of.
There are many behavioral-related hazards, but five stand out as especially dangerous during market corrections and bear markets. Maintaining discipline during elevated financial stress—and resisting emotionally-driven decisions that can derail long‑term goals—is never easy, but it’s always essential.
The research is clear: the costliest mistakes happen when emotions masquerade as insight. In that sense, volatility doesn’t cause those errors—it reveals them.
It’s also fair to say that behavioral risk in investing is a persistent challenge. Markets evolve, but human nature is remarkably consistent, as a recent study suggests (“Behavioral Finance in the Sphere of Investment”). The analysis reviewed 30 studies published between 2020 and 2025 that examined behavioral finance and its influence on investment choices. “The results indicate that investor psychology continues to play a dominant role in financial decision making, with biases shaping investment behaviors across different economic and technological contexts,” the authors report.
The first step in playing defense is recognizing the behavioral traps that can surface in turbulent periods. Here are five to keep on your radar.
Loss Aversion (The Pain of Drastic Drops)
Psychologically, the pain of losing money is roughly twice as intense as the joy of making the same amount. When volatility strikes, this asymmetric pain can trigger a survival instinct, tempting investors to “stop the bleeding.”
The key risk: Selling assets at or near the bottom of a drawdown in pursuit of emotional relief, turning temporary paper losses into permanent capital destruction.
To be clear, selling may be reasonable, even in a downturn. But reducing exposure to risk assets because of a predetermined set of rules may be quite different from selling because you’re triggered by news headlines.
Recency Bias (Extrapolating the Present)
Human brains naturally overweight recent events when forecasting the future. In calm markets, we assume smooth sailing indefinitely; during a sharp correction, it’s all too easy to let the darker angels of your brain assume that the downward trend will continue straight to zero.
The key risk: Forgetting the long‑term historical data on market cycles and regime shifts. This bias makes it especially difficult to maintain a rebalancing schedule, which inherently requires buying assets that have recently performed poorly, and paring back on the strongest performers.
Herding Behavior (Following the Crowd)
When uncertainty peaks, looking to the crowd for validation is a natural human response. If the financial press and broader market are panicking, individual investors often find it difficult to stand firm or look for value.
The key risk: Joining the stampede out of an asset class just as expected risk premiums are rising and prospective long‑term returns are improving.
Action Bias (The Urge to “Do Something”)
During an economic or market shock, sitting still can feel like negligence for some investors. This drive to take control can lead to over‑trading during the worst possible macro environments.
The key risk: Tweaking asset‑allocation models mid‑crisis, over‑hedging after the volatility spike has already occurred, or constantly shuffling positions. This behavior racks up transaction costs, creates tax drag, and typically results in whipsawing the portfolio. Once again, carefully developing an investment strategy before a shock, and sticking to the plan, can be a guardrail.
Information‑Avoidance Bias (Ignoring Negative or Discomforting Data)
This is the opposite of action bias: Some investors manage stress by disengaging entirely—a pattern often referred to as the “ostrich effect.” They stop checking performance metrics, ignore risk reports, and delay necessary portfolio maintenance.
The key risk: Missing critical rule‑based rebalancing windows or overlooking a fundamental shift in macro indicators that genuinely requires a programmatic adjustment to a tactical model.
