Complexity Bias and XEQT: Why Your Brain Rejects the Simplest Path to Wealth

I want to tell you about the night I peaked as a “sophisticated investor.”

It was a Sunday in early 2021, and I was sitting at my desk with three monitors glowing in the dark. One screen had a spreadsheet with fourteen tabs – one for each ETF in my hand-built portfolio. Another had a rebalancing calculator I had spent two weekends building from scratch. The third had a colour-coded calendar showing my quarterly rebalancing dates, dividend reinvestment triggers, and tax-loss harvesting windows.

My portfolio held ten different ETFs. Canadian equities, U.S. equities, international developed markets, emerging markets, Canadian bonds, global bonds, REITs, a small-cap value tilt, a momentum factor fund, and a gold ETF “for tail risk protection.” I had a target allocation for each one, calculated to two decimal places. I had read the academic papers justifying each tilt. I could explain the Fama-French three-factor model at a dinner party (not that anyone ever asked).

I felt brilliant. This was a portfolio designed by someone who truly understood investing. Not some beginner buying a single fund and hoping for the best. This was real portfolio construction.

Then one evening, I did something I had been avoiding for months. I opened a fresh spreadsheet and calculated my actual after-fee, after-tax, after-rebalancing returns since I had built this masterpiece. Then I looked up what XEQT had returned over the same period.

XEQT had beaten me by 1.3% annually. With zero spreadsheets. Zero rebalancing. Zero tax-loss harvesting. Zero effort.

I stared at the screen for a long time. Then I closed all fourteen tabs, sold everything, and bought XEQT. It took about four minutes. The portfolio I had spent hundreds of hours building and maintaining was replaced by a single ticker – and my results immediately got better.

That was the night I learned about complexity bias, and it changed the way I think about investing forever.

1. What Is Complexity Bias?

Complexity bias is the cognitive tendency to trust, prefer, and assign more value to complex solutions over simple ones – even when the simple solution is equally or more effective.

It is not the same as choosing complexity because a situation genuinely requires it. Complexity bias is the irrational preference for complication itself. It is the feeling that a solution cannot possibly be right if it seems too easy. It is the voice in your head that says, “If investing were really this simple, everyone would be rich.”

Psychologists have documented this bias across dozens of domains. In a landmark series of studies by Helena Matute and colleagues at the University of Deusto, participants consistently rated complex explanations as more credible than simple ones, even when both explained the same evidence equally well. The more moving parts an explanation had, the smarter it sounded – and the more people trusted it.

This bias has deep evolutionary roots. For most of human history, the problems we faced were genuinely complex: tracking prey through a forest, navigating social hierarchies, building shelters from available materials. Our brains learned to associate effort and sophistication with better outcomes. In many areas of life, that association still holds. A surgeon who spends twelve years in training really is better than one who watched a YouTube video. A bridge designed by a team of engineers really is safer than one sketched on a napkin.

But investing is one of the rare domains where this intuition is catastrophically wrong. In investing, complexity is not a signal of quality. It is usually a signal of cost, confusion, and underperformance.

2. Complexity Bias Outside of Investing: You Have Seen This Before

Before we dive into portfolios, it is worth seeing how complexity bias operates in other fields. Recognizing the pattern elsewhere makes it easier to spot in your own investing decisions.

Medicine

Studies published in the Journal of Experimental Psychology have shown that patients rate complex treatment plans as more effective than simple ones, even when clinical outcomes are identical. A doctor who prescribes three medications, a dietary supplement, and a specialized exercise routine is perceived as more competent than one who says “take this one pill and go for a daily walk” – even if the outcomes are the same.

Business strategy

McKinsey and Harvard Business Review have both documented how managers gravitate toward complex strategic plans. A 90-page strategy deck with frameworks, matrices, and jargon feels more “rigorous” than a one-page plan with three clear priorities. Yet research on organizational performance consistently shows that companies with simple, focused strategies tend to outperform those with elaborate ones.

Technology

In software engineering, there is a principle called KISS – “Keep It Simple, Stupid.” Experienced developers know that the most elegant code is the simplest code that works. But junior developers (and their managers) often conflate complexity with sophistication. The result is bloated systems that are harder to maintain, more prone to bugs, and slower to adapt.

Cooking

A recipe with 27 ingredients and three-hour prep time feels “gourmet.” A recipe with five ingredients and twenty minutes feels amateurish. But ask any professional chef and they will tell you that the hardest thing to cook well is a dish with very few ingredients, because there is nowhere to hide.

The pattern is always the same: complexity feels like competence, but simplicity requires more confidence and often produces better outcomes.

3. Why Investing Attracts Complexity Bias More Than Almost Any Other Field

Investing is uniquely vulnerable to complexity bias. Several forces converge to make the “more complicated = better” instinct almost irresistible.

The “sophisticated investor” identity

The financial world idolizes complexity. Hedge fund managers with algorithmic strategies. Private equity titans with leveraged buyout models. Venture capitalists with proprietary deal flow. The implicit message is that real investing is complicated – and that if your approach is simple, you are not a real investor.

This ties into what psychologists call identity-protective cognition. Once you identify as a “sophisticated investor,” simplifying your portfolio feels like a demotion. It threatens your self-image. I wrote about this phenomenon in the paradox of simple investing – the strange fact that the smartest move in investing looks, from the outside, like the laziest one.

The financial industry profits from complexity

This is not a conspiracy theory. It is a business model. Every additional product, every new strategy, every layer of complication creates an opportunity for someone to charge a fee. Mutual fund companies charge 2%+ MER on actively managed funds. Financial advisors justify their AUM fees by showing you elaborate portfolio constructions. Robo-advisors layer on portfolio “optimization” to differentiate from a plain ETF purchase.

The entire industry has a financial incentive to convince you that investing is too complicated for you to do alone – and that their complexity is worth paying for. The attention tax of active investing documents what this complexity actually costs you in time, money, and mental energy.

The effort-outcome illusion

In almost every other area of life, more effort produces better results. Study harder, get better grades. Practice more, play better guitar. Work longer hours, earn more money. Our brains have deeply internalized this pattern.

Investing is one of the few domains where this relationship inverts. The more effort you put in – more research, more trading, more portfolio tinkering – the worse your results tend to be. This is so counterintuitive that most people simply refuse to believe it, even after seeing the data. It feels wrong. And because it feels wrong, they add more complexity to compensate.

I explored this in detail in the knowledge trap – the uncomfortable truth that past a certain point, learning more about investing can actually make your returns worse.

Information overload creates the illusion of control

We live in an era of infinite financial information. Real-time stock quotes. Earnings call transcripts. Macroeconomic data releases. Reddit threads. YouTube analysis. Bloomberg terminals. AI-powered stock screeners.

All of this information makes you feel like you should be doing something with it. Like ignoring it is irresponsible. Like the person who reads all of it and builds a complex strategy around it must be doing better than the person who just buys XEQT and goes for a walk.

But information and insight are not the same thing. Most financial information is noise, not signal. And processing noise does not make you a better investor – it just makes you a busier one.

4. The Cost of Complexity: A Side-by-Side Comparison

Let me put some concrete numbers on what complexity actually costs. Here is a comparison between a complex multi-ETF portfolio and a single XEQT holding, assuming a $200,000 portfolio over 10 years.

Look at that last row. The complex portfolio does not reliably beat the simple one. In fact, after accounting for the tax drag of frequent rebalancing, the bid-ask spread costs across ten positions, and the inevitable behavioural errors that come with having more decisions to make, the complex portfolio often underperforms.

And that is before you assign any value to the 30-50 extra hours per year you spend managing it. If your time is worth even $30 an hour, that is $900-$1,500 per year in opportunity cost – on a portfolio that is not performing any better.

The complexity is not free. It is expensive. And it is not buying you anything.

5. Real-World Evidence: Complexity Fails at Scale

If complexity worked, the most complex investors in the world should be the most successful. Let us see how that theory holds up.

Warren Buffett’s million-dollar bet

In 2007, Warren Buffett made a famous $1 million bet with Protege Partners, a fund-of-hedge-funds firm. Buffett bet that a simple S&P 500 index fund would outperform a hand-picked basket of five hedge funds over ten years. These hedge funds employed the most complex strategies imaginable: long-short equity, global macro, quantitative models, derivatives overlays, and leverage.

The result? Over the ten-year period from 2008 to 2017, the S&P 500 index fund returned 125.8%. The five hedge funds returned an average of 36%. The simple approach did not just win – it won by a landslide. And the hedge funds charged “2 and 20” (2% management fee plus 20% of profits) for the privilege of underperforming a fund that charged 0.04%.

SPIVA scorecard

The SPIVA Canada Scorecard consistently shows that the vast majority of actively managed funds – employing teams of analysts, proprietary research, and complex strategies – fail to beat their benchmark indices over any meaningful time horizon. Over 20 years, roughly 90-95% of active managers underperform.

Yale Endowment model versus simple indexing

For years, the “Yale Model” pioneered by David Swensen was held up as the gold standard of complex institutional investing – alternative assets, private equity, venture capital, timber, real estate. And it worked brilliantly for Yale, which had access to top-tier fund managers and could negotiate fee structures unavailable to regular investors. But when other endowments tried to replicate the model, most failed. A study by the National Association of College and University Business Officers found that the majority of endowments employing complex alternative strategies underperformed a simple 60/40 index portfolio.

Complexity worked for Yale because Yale had unique advantages. You and I do not.

The average investor

DALBAR’s annual Quantitative Analysis of Investor Behavior consistently shows that the average investor dramatically underperforms the very indices their funds track. Over the 20-year period ending in 2023, the average equity fund investor earned roughly 5.5% annually, while the S&P 500 returned roughly 9.7%. The gap – roughly 4.2% per year – is almost entirely explained by complexity-driven behaviour: market timing, fund switching, chasing hot sectors, and reacting to news.

The data is overwhelming and consistent: the more complex the strategy, the wider the gap between potential returns and actual returns.

6. The Psychological Comfort of Complexity

If complexity does not produce better returns, why do so many smart people insist on it? Because complexity serves a psychological need that has nothing to do with performance.

“If it were this simple, everyone would do it”

This is the most common objection I hear. And on the surface, it sounds logical. If buying one ETF and holding it forever were really the optimal strategy, surely the market would have figured this out and the opportunity would disappear.

But the logic does not hold. The opportunity does not disappear because the hard part of simple investing is not intellectual – it is behavioural. Everyone knows they should eat less and exercise more. The simplicity of the solution does not make it easy to follow. Similarly, everyone who reads this blog knows they should buy XEQT and hold it for decades. The reason most people do not is not that the strategy is flawed. It is that human psychology makes simplicity feel uncomfortable.

Complexity as emotional armour

When you have a complex portfolio, a market downturn feels less threatening. You can tell yourself, “Well, my emerging markets allocation is down, but my gold hedge is up, and my factor tilt should outperform in a recovery.” All those moving parts give you something to analyze, adjust, and control. They distract you from the terrifying simplicity of what is actually happening: the market went down and you just have to wait.

With XEQT, there is nowhere to hide. It dropped 15%? Your entire portfolio dropped 15%. There is no rebalancing trick, no tactical adjustment, no sector rotation to make you feel like you are doing something. You just sit there and wait. And that requires a kind of psychological discipline that complexity never asks of you.

The sunk cost of expertise

If you have spent months or years learning about factor investing, reading academic papers, building spreadsheets, and optimizing your multi-ETF portfolio, switching to XEQT feels like an admission that all that effort was wasted. It feels like giving up. Nobody wants to admit they spent two hundred hours on a project that could have been replaced by a four-minute trade.

This is where complexity bias intersects with the IKEA effect – the tendency to overvalue things you built yourself. Your custom portfolio feels more valuable precisely because you put work into it, regardless of whether it actually performs better.

7. Why “Simple” Is Actually the Hardest Strategy

Here is the paradox that complexity bias does not want you to see: simple investing is intellectually easy but behaviourally brutal.

Buying XEQT takes five minutes. Holding XEQT through a 30% crash takes every ounce of discipline you have. And that is the real challenge – not designing the perfect portfolio, but having the emotional resilience to stick with a simple plan when everything inside you is screaming to do something.

Consider what “just hold XEQT” actually requires:

• Watching your portfolio drop $50,000 in a month and doing nothing. Not selling. Not switching to bonds. Not “waiting for the bottom.” Nothing.

• Ignoring your coworker who just made 40% on a meme stock. Not wondering if you should have a “fun money” account. Not feeling like you are missing out.

• Contributing the same amount every month regardless of headlines. Tariffs, recessions, wars, pandemics – your automatic purchase goes through regardless.

• Not checking your portfolio. Or if you do check, closing the app without making changes.

• Doing this for 20, 30, 40 years. Not for a few months until you get bored. For decades.

That is not easy. It is, in fact, one of the hardest things you can do with money. Doing less beats doing more – but doing less requires more willpower than doing more.

The complexity investor stays busy. They have rebalancing to do, research to read, allocations to adjust. They are always doing something, and that activity provides psychological comfort. The XEQT investor sits still while the world burns and rebuilds around them. That takes real strength.

The difficulty of simple investing is not in the strategy. It is in the silence.

8. How to Overcome Complexity Bias: A Practical Guide

Knowing about complexity bias does not make you immune to it. You need practical strategies to counteract it when it inevitably creeps back in. Here is what has worked for me.

Step 1: Recognize the bias in real time

The next time you feel the urge to “improve” your portfolio, pause and ask yourself three questions:

1. Am I adding complexity because the data shows it will improve my returns? Or because it feels like it should?
2. Can I point to a specific, quantifiable benefit this change will produce?
3. Would I recommend this change to a friend who wanted the simplest possible path to wealth?

If you cannot answer “yes” to all three, you are probably being driven by complexity bias rather than evidence.

Step 2: Measure results, not effort

Start tracking your portfolio’s performance against a simple XEQT benchmark. Not just the returns – also track the time you spend. Calculate your “hourly rate” from investing: how much extra return (if any) did your complexity generate, divided by the hours you spent on it?

When I did this calculation honestly, my complex portfolio was generating roughly -$45 per hour of effort. I was literally paying for the privilege of underperforming.

Step 3: Calculate the attention tax

Every minute you spend on your portfolio is a minute you are not spending on something else. The attention tax is the total cognitive and time cost of your investment strategy.

Make a list of everything your complex strategy requires:

• Reading financial news and earnings reports
• Monitoring individual holdings
• Researching potential new positions
• Calculating rebalancing trades
• Executing rebalancing trades
• Tracking adjusted cost base for tax purposes
• Worrying about whether your allocations are still optimal
• Feeling guilty when you skip a rebalancing date

Now estimate the hours per month. Multiply by your hourly rate (or what you could earn doing something else). That is the true cost of your complexity – and it almost never shows up in a performance comparison.

Step 4: Start simple. Add complexity only when there is a proven reason.

If you are building a portfolio from scratch, start with XEQT. Just XEQT. Live with it for a year. Track the returns. See how it feels.

After a year, if you can identify a specific, evidence-based reason to add complexity – not a feeling, not a hunch, not something you read on Reddit – then consider it. But the burden of proof should be on the complexity, not on the simplicity.

In my experience, after a year of holding just XEQT, the urge to complicate things fades dramatically. You realize the returns are good. The stress is low. The free time is abundant. And you start to see complexity for what it usually is: expensive, time-consuming, and unnecessary.

Step 5: Embrace the boredom

The best investment strategy is boring. That is not a bug – it is the whole point. If your portfolio is exciting, something is probably wrong. Analysis paralysis comes from having too many options. Complexity bias comes from distrusting the simple ones. The antidote to both is the same: accept that boring is beautiful.

9. “But My Situation Is Different”

This is complexity bias’s favourite disguise. It shows up wearing a mask of reasonableness, whispering that the simple approach works for other people but not for you, because your situation is uniquely complex.

Let me address the most common versions:

“I have a high income, so I need a more sophisticated tax strategy.” Maybe. But your tax strategy and your investment strategy are separate things. You can hold XEQT inside a carefully optimized TFSA/RRSP/non-registered structure and get all the tax benefits without adding portfolio complexity. The tax wrapper can be smart. The investment inside it can be simple.

“I’m close to retirement, so I need more than just equities.” Fair point. Adding a bond allocation as you approach retirement is a legitimate reason to hold more than one fund. But that is one additional fund (like XBAL or a bond ETF) – not a reason to build a ten-position portfolio with factor tilts and alternatives.

“I have a large portfolio, so the savings from a lower-cost DIY approach justify the complexity.” Run the actual numbers. On a $500,000 portfolio, the difference between XEQT’s 0.20% MER and a DIY portfolio at 0.10% MER is $500 per year. Are you certain your DIY portfolio will outperform XEQT by at least $500 per year after rebalancing costs, tax drag, and behavioural errors? Most people cannot honestly say yes.

“I work in finance, so I have an informational edge.” The research says otherwise. Financial professionals are just as susceptible to behavioural biases as everyone else – and some studies suggest they may be even more susceptible to overconfidence bias because of their domain knowledge.

In nearly every case, “my situation is different” is just complexity bias finding a plausible excuse to do what it was going to do anyway.

10. XEQT’s Simplicity Is a Feature, Not a Bug

Let me close with the most important reframe in this entire post.

When you look at XEQT – one ticker, one fund, one decision – your brain’s complexity bias whispers that it cannot possibly be enough. That serious wealth requires serious complexity. That a single ETF is a beginner’s tool, a training wheel, something you will eventually outgrow.

But XEQT is not simple because it is unsophisticated. It is simple because all the sophistication has been buried beneath the surface, handled for you by BlackRock’s portfolio managers. Inside that single ticker, you own over 9,000 stocks across 49 countries. The geographic allocation is professionally determined and automatically rebalanced. The underlying index methodology is backed by decades of academic research. The fund structure is optimized for tax efficiency and cost minimization.

XEQT is not the absence of complexity. It is complexity that has been solved, packaged, and handed to you for 0.20% per year. You are not avoiding sophistication by buying it. You are outsourcing the sophistication to people who do it better than you or I ever could – and keeping the one job that actually matters: staying invested for the long term.

The simplicity is the product. The discipline to hold it is the work. And the results speak for themselves.

I spent years adding complexity to my portfolio because complexity felt like progress. It felt like mastery. It felt like I was taking investing seriously. But the numbers never supported that feeling. They never do.

The most sophisticated thing I ever did as an investor was stop trying to be sophisticated.

If you are sitting at your desk right now with a multi-tab spreadsheet, a rebalancing calendar, and a nagging feeling that all of it is not actually helping – trust that feeling. Run the numbers. Compare your returns to XEQT. And if the simple path would have served you better, have the courage to take it.

Your brain will resist. Complexity bias will whisper that you are giving up, dumbing down, settling for mediocrity. But the data, the research, and the experience of millions of investors all point to the same conclusion: simplicity wins. Not because investing is easy, but because the hard part was never the portfolio design. It was always the patience.

Just buy XEQT. And then go live your life.

Related Reading

If this post resonated with you, these articles go deeper on the topics covered here:

• What Is XEQT? A Complete Guide – everything you need to know about Canada’s most popular all-in-one ETF
• The Paradox of Simple Investing – why the smartest strategy looks like the laziest one
• The Knowledge Trap: Why Learning More About Investing Makes You Worse at It – what happens when expertise backfires
• Analysis Paralysis: How Overthinking Is Killing Your XEQT Returns – the cost of waiting for the perfect strategy
• The Attention Tax of Active Investing vs. XEQT – what your portfolio complexity is really costing you
• Financial Minimalism and XEQT: Why Less Really Is More – the minimalist approach to building wealth
• Is XEQT the Only ETF You Need? – the case for a true one-fund portfolio