diversification

28 Investment Principles That Actually Work When Markets Don't Cooperate

Article # 442

I've watched families navigate decades of volatility: crashes, recoveries, euphoria, panic. The ones who preserve wealth across generations don't have secret information or perfect timing. They follow simple rules, consistently.

February has 28 days. To ring it in, here are 28 guiding principles that have stood the test of time regardless of market activity.

1.       The market rewards patience, not prediction.

Most noise isn't information. The constant stream of commentary, analysis, and breaking news creates the illusion that staying informed means staying ahead. It doesn't. The market moves on fundamentals that reveal themselves slowly, not on headlines that change hourly.

2.       Focus on what you can control: Costs, discipline, diversification, behaviour.

You cannot control returns. You cannot control when recessions arrive or when bull markets end. But you can control how much you pay in fees, how consistently you invest, how broadly you spread your risk, and how you respond when fear or greed takes hold.

3.       You don't need to beat the market. You just need to capture it.

The obsession with outperformance drives investors towards complexity, higher costs, and ultimately, disappointment. Capturing market returns through low-cost, diversified portfolios has built more wealth over time than the pursuit of alpha ever has.

4.       The simplest portfolio is often the smartest.

Complexity rarely adds value. It adds cost, confusion, and opportunity for error. A straightforward allocation across global equities and bonds, rebalanced systematically, has outperformed the vast majority of elaborate strategies.

5.       Volatility is the price of admission.

Don't demand returns without accepting the ride. Equities deliver premium returns over time, because of fluctuations in the short term. If you cannot stomach the volatility, you don't deserve the returns.

6.       Time in the market matters more than timing the market. Always.

Missing just the 10 best days over a 20-year period can cut your returns nearly in half. Funnily enough, the best days often follow the worst ones – so it’s hard to capture them after getting cold feet on the downswing. Staying invested through the chaos is what separates wealth-builders from market-timers.

7.       Diversification is a dark horse.

Its power is revealed over decades, not days. When one asset class stumbles, another steadies the ship. The benefit isn't dramatic in any one year, but over a lifetime of investing, it's the difference between weathering storms and being swept away by them.

8.       Your plan should be built on evidence, not emotion.

Especially when emotions run high. When markets crash, fear whispers that this time is different and worse than any before. When markets soar, greed tells you that you're missing out. Evidence and decades of market history tell a different story – a much more trustworthy one.

9.       Chasing performance is a tax on impatience.

Last year's winners become this year's laggards with predictable regularity. By the time a fund or strategy appears on a "best performer" list, the opportunity has usually passed. Avoid getting swept up in the furore.

10.  The market has already priced in what everyone knows.

You don't need to outguess it. If information is public, it's already reflected in prices. Your edge as an investor isn't superior information, it's superior behaviour.

11.  A disciplined strategy beats a brilliant prediction. Every time.

Predictions fail. Discipline endures. The investor who follows a consistent plan through all market conditions will outperform the ‘strategist’ who tries to predict turning points.

12.  Your behaviour matters more than your products.

Panic is more expensive than fees: selling in a downturn locks in losses, while buying at market peaks locks in mediocre returns. Managing your behaviour by staying calm, and staying invested, matters far more than optimising your expense ratio by a few measley basis points.

13.  You don't need the perfect moment.

The moment you start is perfect enough. Markets climb over time. Waiting for a correction before investing often means waiting forever. Start now. Adjust as you go.

14.  Rebalancing is the quiet hero of long-term returns.

It forces buy-low, sell-high. When equities surge, rebalancing trims them back. When they crash, rebalancing buys more. It's counter-intuitive, uncomfortable… and extraordinarily effective over time.

15.  The best portfolios feel boring.

Boredom is not a bug, it's a feature. If your portfolio keeps you up at night with excitement, you’re probably taking on unnecessary risk. Wealth is built slowly, quietly, and without drama.

16.  Markets recover more often than they collapse.

History is your friend. Every bear market in history has eventually given way to a new bull market. Crashes feel permanent in the moment. They never are – as the adage goes, “this too shall pass.”

17.  Ignore headlines.

They're written to sell attention, not build wealth. Financial media thrives on urgency and alarm. Your portfolio should thrive on patience and perspective.

18.  Compounding works best when you don't interrupt it.

Let time do the heavy lifting. Albert Einstein allegedly called compound interest the eighth wonder of the world. But, it only works if you leave it alone – every time you exit the market, you reset the clock.

19.  Costs compound too.

Costs compound just like returns. Pay for advice that adds value, not for products that don't. The difference between value and waste always reveals itself in the fullness of time.

20.  Bad days don't destroy portfolios. Bad decisions do.

Markets fall. That's normal, and things will swing back the other way. Selling during the fall, abandoning your plan, or fleeing to cash – those are the decisions that inflict permanent damage.

21.  Not every risk deserves a reward.

Factor premiums do. Stocks are riskier than bonds, so they should deliver higher returns. Small-cap and value stocks have historically outperformed over long periods. These are risks worth taking. Concentrated bets on individual stocks or sectors? Not so much.

22.  Your portfolio should be built around you, not around the news cycle.

Your goals, your time horizon, and your risk tolerance should dictate your allocation. Not the latest economic forecast or geopolitical crisis.

23.  You don't need to predict the future.

…But you do need a strategy that survives it. Robust portfolios aren't built on forecasts. They're built on diversification, discipline, and the recognition that uncertainty is permanent.

24.  Stay invested, stay diversified, stay disciplined.

The rest is commentary. If you do these three things consistently, you will be fine. Better than fine, in fact. You'll be wealthier than the vast majority of investors who spend their lives chasing the next opportunity.

25.  Wealth isn't created in moments of excitement.

It's created in years of consistency. The investors who succeed aren't the ones who make brilliant trades or perfectly time the market. They're the ones who show up, year after year, regardless of conditions. Consistency compounds.

26.  Your worst investing day feels catastrophic. Your best investing decade feels inevitable.

Perspective matters. In the moment, a 20% drawdown feels like the end. Twenty years later, it's a footnote. Keep the long view. Stay the course.

27.  Successful investors are more patient than ‘smart’.

Intelligence helps, but temperament wins out every time. The ability to sit still, to do nothing when everyone else is panicking or euphoric, is worth more than any financial qualification.

28.  Markets don't care about your timeline. Build a plan that doesn't care about the markets.

You might need money in five years for a house deposit or in thirty years for retirement. The market will do what it does regardless. Structure your portfolio around your needs, not market predictions, and you'll sleep better through every cycle.

Remember: Markets will always be chaotic. Your response doesn't have to be.

Follow the rules (and seek professional advice)

These principles work. But they work best when you have someone in your corner who isn't conflicted by commissions, product sales, or institutional agendas.

Seek independent, impartial advice that puts you first and foremost. You are the sun, not the moon: your financial plan should orbit around you, your goals, your circumstances. Not around what someone else needs to sell.

Nick Stewart

(Ngāi Tahu, Ngāti Huirapa, Ngāti Māmoe, Ngāti Waitaha)

Financial Adviser and CEO at Stewart Group

  • Stewart Group is a Hawke's Bay and Wellington based CEFEX & BCorp certified financial planning and advisory firm providing personal fiduciary services, Wealth Management, Risk Insurance & KiwiSaver scheme solutions.

  • The information provided, or any opinions expressed in this article, are of a general nature only and should not be construed or relied on as a recommendation to invest in a financial product or class of financial products. You should seek financial advice specific to your circumstances from a Financial Adviser before making any financial decisions. A disclosure statement can be obtained free of charge by calling 0800 878 961 or visit our website, www.stewartgroup.co.nz

  • Article no. 442


Should I Invest in What I Love? Product Affection vs Investment Logic

Personal product preferences are often the worst possible guide to investment decisions.

I remember when my family first got a GoPro. Revolutionary technology, stunning footage – everyone wanted one. Naturally, I thought: "This company is going places. Maybe I should buy shares." It's a seductive logic: if I love the product, surely others will too. A decade later, I'm thankful I didn't act on that impulse.

This instinct to invest in what we know and love feels intuitive. We use the products, we understand them, we see their value. But this emotional connection – what behavioural economists call "familiarity bias" – is precisely what makes it dangerous.

Back in 2014, GoPro went public and quickly hit a market capitalization of $10 billion with virtually no competition. Today? The stock trades around $1.87 per share – down 98% from its peak, with over $9.7 billion in market value lost.

What went wrong?

Smartphones killed the action camera star. Modern phones became waterproof, gained multiple lenses, and developed image stabilisation that rivals dedicated cameras. GoPro thought they were competing against other action cameras when they were actually competing against the most successful consumer device in history.

But here's the deeper lesson: loving a product tells you nothing about the company's competitive position or long-term viability. A great product is necessary but far from sufficient for investment success. In GoPro's case, every smartphone manufacturer became their competitor, each with deeper pockets and products consumers were already buying.

The Pattern Repeats Closer to Home

This isn't just an overseas story. Take My Food Bag – during COVID lockdowns, it seemed genius. The company went public in March 2021 at $1.85 per share, raising $342 million. Customers loved the service and bought shares. Many retail investors had enjoyed watching co-founder Nadia Lim cook on TV for years – hardly grounds for a wise investment decision. The result? Shares now trade around 25 cents – an 86% decline. As one fund manager noted, "It was a classic private equity exit, which has seen a lot of retail investors lose out."[1]

The timing seemed perfect. Lockdowns had created new habits. People were cooking at home more. The convenience model made sense. But investors failed to ask: what happens when lockdowns end? Is this a permanent behaviour shift or a temporary adaptation? How defensible is the business model? These are the uncomfortable questions that emotional attachment prevents us from asking.

As one fund manager noted, "It was a classic private equity exit, which has seen a lot of retail investors lose out."

Then there's Ryman Healthcare, beloved by many Kiwi families for good reason. My own family experienced the amazing care and kindness shown towards my late father during his time in the dementia care unit at Ryman in Havelock North. The quality of their villages is genuinely impressive. Yet despite these strengths, the stock hit $10.87 in December 2019 and now trades around $2.87 – down 74%. The investment thesis crumbled under construction delays and regulatory challenges, demonstrating that exceptional service doesn't automatically translate into strong investment returns.

This one hits close to home because the service was excellent. But gratitude and investment logic operate in different domains. A company can deliver outstanding customer experiences while simultaneously facing operational headwinds that undermine shareholder returns.

These three examples share a common thread: product or service quality created an emotional connection that clouded rational investment analysis.

The Evidence Against Emotional Investing

Behavioural finance research identifies "familiarity bias" as a major driver of poor investment decisions, where investors favour what they know rather than what performs best.[2] This bias is particularly pronounced amongst long-term investors who believe they're securing against volatility when they're actually concentrating risk.

The evidence against stock picking is overwhelming:

An Arizona State University study by Professor Hendrik Bessembinder examining over 28,000 stocks from 1926 to 2024 found that just 4% of firms created all net wealth in the U.S. stock market. The remaining 96% collectively matched Treasury bills over their lifetimes, and the majority of individual stocks actually reduced shareholder wealth compared to holding cash.[3]

Think about that. If you picked a stock at random, you'd have better than even odds of underperforming cash. The market's impressive returns come from a tiny fraction of companies – and identifying them in advance is nearly impossible.

Professional fund managers fare no better. S&P Dow Jones Indices' SPIVA Scorecard shows that after 10 years, approximately 85% of large-cap funds underperform the S&P 500, and after 15 years, around 90% trail the index.[4] Even Warren Buffett admits: "In 58 years of Berkshire management, most of my capital-allocation decisions have been no better than so-so."[5]

These aren't amateur investors. These are professionals with research teams, Bloomberg terminals, insider access, and decades of experience. If they can't beat a simple index fund, what makes individual investors think they can, especially when driven by product affection rather than analysis?

The Smart Money Questions

Instead of asking "Do I love this product?", evidence-based investors ask: How big is the addressable market? What prevents competitors from copying this? How strong are the financials? Is the company innovating fast enough? What could make this product obsolete?

These questions are deliberately uncomfortable because they force you to look beyond your emotional attachment. They require research, analysis, and a willingness to acknowledge uncertainty. Most importantly, they shift the focus from "I like this" to "can this company maintain a durable competitive advantage?"

The answers usually point to the same solution: diversification. Diversified index funds consistently outperform stock picking over the long term, providing market-matching returns while reducing the risk of catastrophic losses from individual stock failures.[6]

Diversification isn't glamorous. There's no story to tell at dinner parties about your clever stock pick. But it's precisely this lack of excitement that makes it effective. By owning the entire market, you guarantee you'll own the 4% of companies that generate all the wealth creation, without needing to predict which ones they'll be.

As a fee-only adviser working with evidence-based strategies, the real value isn't in chasing hot stocks or validating product obsessions. It's in building a robust financial plan grounded in decades of research, then maintaining discipline through market noise and emotional temptation.

This discipline is harder than it sounds. When GoPro was soaring, when My Food Bag was listing during lockdowns, when you're genuinely grateful for care received – the emotional pull to invest is powerful. It feels like you have special insight. You don't. You have an emotional connection clouding your judgment.

The most valuable thing a good adviser provides isn't stock tips or market predictions. It's the voice of reason when your emotions are screaming at you to invest in what you love. It's the person who asks the uncomfortable questions: "Have you analyzed the competitive landscape? What's your exit strategy? How does this fit your overall plan?" These questions aren't exciting, but they're essential.

Seek wise counsel, commit to a plan that aligns with your goals, and redirect that energy from stock-picking to living your life. Enjoy the products you love. Be grateful for excellent service. Just don't confuse these feelings with investment insight.

Your future self will thank you for choosing evidence over emotion.

Nick Stewart

(Ngāi Tahu, Ngāti Huirapa, Ngāti Māmoe, Ngāti Waitaha)

Financial Adviser and CEO at Stewart Group

  • Stewart Group is a Hawke's Bay and Wellington based CEFEX & BCorp certified financial planning and advisory firm providing personal fiduciary services, Wealth Management, Risk Insurance & KiwiSaver scheme solutions.

  • The information provided, or any opinions expressed in this article, are of a general nature only and should not be construed or relied on as a recommendation to invest in a financial product or class of financial products. You should seek financial advice specific to your circumstances from a Financial Adviser before making any financial decisions. A disclosure statement can be obtained free of charge by calling 0800 878 961 or visit our website, www.stewartgroup.co.nz

  • Article no. 437


References

  1. My Food Bag Group Limited. (2024-2025). Financial Results and Market Updates. NZX Announcements. Retrieved from https://investors.myfoodbag.co.nz/

    • Devon Funds Management. (2025). "My Food Bag Investment Analysis." RNZ Business Interview, May 22, 2025.

  2. Huberman, G. (2001). Familiarity breeds investment. Review of Financial Studies, 14(3), 659–680. https://doi.org/10.1093/rfs/14.3.659

    • Chew, S.H., Li, K.K., & Sagi, J. (2023). Home bias explained by familiarity, not ambiguity. Social Science Research Network. https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3870716

    • De Vries, A., Erasmus, P.D., & Gerber, C. (2017). The familiar versus the unfamiliar: Familiarity bias amongst individual investors. Investment Analysts Journal, 46(1), 24-39.

  3. Bessembinder, H. (2024). Shareholder wealth enhancement, 1926 to 2022 (Updated through 2024). Arizona State University, W.P. Carey School of Business. Retrieved from https://wpcarey.asu.edu/department-finance/faculty-research/do-stocks-outperform-treasury-bills

    • Bessembinder, H. (2018). Do stocks outperform Treasury bills? Journal of Financial Economics, 129(3), 440-457.

  4. S&P Dow Jones Indices. (2024). SPIVA U.S. Scorecard Year-End 2024. Retrieved from https://www.spglobal.com/spdji/en/documents/spiva/spiva-us-year-end-2024.pdf

  5. Berkshire Hathaway Inc. (2022). Letter to Shareholders. Annual Report 2022.

  6. Malkiel, B.G. (2019). A random walk down Wall Street: The time-tested strategy for successful investing (12th ed.). W.W. Norton & Company.

    • Bogle, J.C. (2017). The little book of common sense investing: The only way to guarantee your fair share of stock market returns (10th anniversary ed.). John Wiley & Sons.

    • Fama, E.F., & French, K.R. (2010). Luck versus skill in the cross-section of mutual fund returns. The Journal of Finance, 65(5), 1915-1947.

 

 

The lesser-known link between investment and return

"Investment" actually has two interrelated meanings: a physical investment (machinery, building, cars etc.) and financial investment (stocks and bonds), which lays claim on physical investment and the income (aka "return") it generates. So what is the lesser-known link between investment and return? Productivity.

Slashed dividends | Covid-19 Special Focus

Dividend stocks are a staple of every income investor, and they can play an important role in any portfolio, regardless of age and financial circumstances. But it is very much possible that dividend investors can fall into the trap of hindsight bias if they are not careful and sufficiently diversified.

Diversification a Great Luxury

New Zealanders are not keen on diversifying. NZX makes up 0.01% of the world’s share market capitalisation, but most New Zealand investor portfolios are overly weighted to the home market. In other words, a New Zealand investor with a strong home bias would have just a 7% allocation to technology, compared to approximately 16% in the global portfolios.