Time not timing: The case for long-term investing

Market volatility can test even the most disciplined investors, but reacting to short-term noise often comes at a long-term cost. Drawing on historical market data, this article shows why staying invested, resisting the urge to time the market, and maintaining diversification can be critical to building durable wealth over time.

In investing, movement is often mistaken for progress. Market headlines and fluctuations, economic surprises, and geopolitical soundbites create a near-constant noise, tempting even seasoned investors to react emotionally. Yet successful investing is rarely about reacting to every twist and turn. It’s about maintaining a diversified strategy that can help offset behavioural instincts and allow the effects of compounding to work uninterrupted. 

This paper argues that staying invested through market fluctuations, rather than reacting to short-term market noise, is essential for long-term investment success. Drawing on historical data for the MSCI World Index (Gross Total Return, USD) and Bloomberg Global Aggregate Bond Index (USD) from January 1990 to March 2026, we demonstrate how patient and disciplined investors are rewarded for their fortitude over the long term. Over extended periods, it is this steadfast approach, rather than impulsive shifts, that reliably builds lasting wealth.

The unseen cost of interruption

Compounding is a powerful force but is also a fragile one. As Charlie Munger wisely noted, “The first rule of compounding: Never interrupt it unnecessarily”. Yet when markets decline, even rational investors often abandon their plans, driven by fear into making costly decisions.

Time is compounding’s greatest ally. The longer capital stays invested, the more effectively it grows. However, attempts to dodge downturns or wait for “better entry points” often backfire, interrupting the very process that builds wealth.

A natural reaction is selling during a market dip and waiting on the sidelines for calm to return. These seemingly prudent moves, born from panic or discomfort with volatility, often exact a high price. The chart below illustrates this cost. It compares the growth of USD 100,000 for a disciplined investor who remains fully invested, versus scenarios where an investor reacts to a quarterly loss of 10% or more by selling and sits out for several months, earning no return during that time. The reactionary approach often fails because most market dips are false alarms—noise, rather than signals of a lasting decline.

The costs of reacting to market volatility are not merely theoretical abstractions. Recent market history provides vivid evidence of how quickly the market can punish those who sit out for “clarity”. Investors who abandoned their plans during the COVID-19 crisis in Q1 2020, or the rate shock in Q3 2022, or the more recent ‘Liberation Day’ tariff crash in April 2025, would have been whipsawed by swift recoveries. For context, the MSCI World Index has generated total returns of 50% and 28% (in USD) in the 12-month period following its March 2020 and September 2022 lows, respectively. Most recently, those who exited during the tariff-induced volatility of last April missed a recovery of over 21% in the subsequent 3 months.

The problem can be mitigated when investors become less reactive. While extreme events may still breach any signal, ignoring smaller fluctuations in favour of a more significant threshold—such as a 15% quarterly loss—can make long-term portfolio outcomes more resilient, as shown in the subsequent chart. Over the period analysed, there were 10 instances where quarterly losses exceeded 15%, but this number jumped to 29 when the threshold dropped to 10%. This increase in trading not only hinders compounding but can also create tax liabilities and transactions costs that further erode returns.

The lesson is clear: volatility is the price investors pay to harness compounding’s full power. Those who accept this inevitable turbulence and remain disciplined in their approach stand a greater chance of being rewarded with wealth that far exceeds what any reactionary selling strategy may deliver.

The myth of market timing

Defensive selling is reactive—reacting to losses after they occur, in response to volatility. On the other hand, market timing is proactive—selling before expected downturns and buying before recoveries. While appealing, this strategy demands extreme precision. Can this proactive market timing strategy succeed where defensive reactions fail?

The allure of market timing is understandable. A few days often account for most returns. Missing them can severely impact performance. Sidestepping the worst months while capturing the best ones would theoretically generate spectacular results but is highly unlikely. While this approach is oversimplified as noted by researchers at AQR , the underlying challenge remains—executing market timing requires extreme precision. 

The chart below illustrates this point, contrasting the annualized returns since January 1990 for a fully invested portfolio with scenarios where an investor misses a handful of the market’s best-performing months. The penalty for being on the sidelines, even briefly, may be severe. While missing the best months could be offset by avoiding the worst, the odds, while somewhat improved, remain challenging.

Even when investors entrust their portfolios to skilled active managers, their own behaviour can still undermine performance. A common pitfall is performance chasing—reallocating capital toward recently outperforming asset classes or funds while pulling away from those that have underperformed. This reactive approach often results in buying high and selling low, inadvertently forcing managers to invest in assets that have already become expensive and divest from those that may be poised for recovery. The consequences of poorly timed investment decisions become evident when comparing a fund’s time-weighted return (TWR)—which reflects the manager’s performance—with its money-weighted return (MWR), which captures the actual returns experienced by the average investor. Studies such as Morningstar’s “Mind the Gap” consistently highlight this behavioural shortfall: across investment categories, investor returns (MWR) tend to lag behind fund returns (TWR), largely due to mistimed entries and exits driven by emotion rather than strategy.

This gap is less about the manager’s strategy and more about the timing of the investor’s decisions. And the real risk isn’t in trying to time the market but in doing so without a clear framework, often guided by emotion than evidence.

Furthermore, as research by Dichev & Zhen (2022)  shows, this return-chasing behaviour not only lowers returns but also increases the volatility actually experienced—ironically, the very risk most investors hope to dodge. Avoiding this costly mistake often comes down to staying invested and resisting the urge to react.

The final section explores how maintaining a well-diversified portfolio can help investors staying the course by softening the behavioural triggers that so often lead to avoidable mistakes. 

Stay diversified. Stay disciplined.

Diversification is often described as the only “free lunch” in investing. It is more than risk spreading—it reduces emotional strain. When a portfolio experiences fewer and smaller drawdowns, an investor is far less likely to feel the compulsion to act at the wrong time—and that discipline is often the key to long-term success.

For example, a diversified mix of 60% equities and 40% bonds has historically delivered significantly lower drawdowns than an all-equity portfolio. While equities alone suffered quarterly losses of 10% of more with some regularity, a diversified blend reduces both the depth and frequency of such declines as shown below. In practical terms, that means fewer moments when investors feel the urge to “do something”—sell, switch, or second-guess.

Reducing emotional stress during market volatility can lead to meaningful financial benefits, as many poor investment decisions are made in moments of panic. The chart below illustrates this by revisiting our “panic selling” scenario where an investor sells after a quarterly loss of 10% or more and sits out for three months. While this reactionary approach damages returns in both cases, the diversified investor fares much better simply because they had far fewer temptations to abandon their plan. Notably, in our study period from February 1990 to February 2026, the all-equity portfolio triggered panic sales 27 times, and the diversified ’60-40¹’ portfolio, a mere seven. 

Ultimately, diversification and discipline are closely linked. The former is the structural tool that supports the latter. For most investors, creating a portfolio that gives them fewer reasons to react is a far more reliable path to success than attempting to perfectly time their reactions.

Building wealth by staying the course

Markets will rise and fall. Headlines will swirl. Today, the ongoing Middle East conflict and the resulting energy shock leave investors at a familiar juncture—one that echoes many moments of uncertainty before it. While the full extent of this episode is still unfolding, it poses the same enduring question of resolve that past crises have tested. History may not repeat itself, but it often rhymes.

And if history is any guide, wealth is rarely built by predicting markets—it is built by remaining invested through them. Long-term investing works not because it’s easy, but because it focuses on long-term market fundamentals rather than daily fluctuations. For the thoughtful investor, the true edge lies not in timing the market, but in remaining committed, diversified, and disciplined through every phase of the cycle.

Maintaining emotional discipline is critical.  Resisting impulsive reactions to market downturns such as panic selling may help prevent irrational decisions and potential losses. Market volatility is an inherent aspect of investing. Over time, adhering to a long-term, diversified strategy has proven to be one of the most effective ways to navigate uncertainty and build durable wealth.