When Portfolios Fail Quietly
Last week I touched on Sharpe’s work and the way his theory has been quietly misunderstood over time.
I suggested that investment portfolios should ultimately be assessed by the outcomes they deliver, not by how smooth or comfortable the journey appears along the way.
And once you start looking at portfolios like that, something else becomes very difficult to ignore.
The Quiet Kind of Failure
Most retirement portfolios don’t fail in dramatic fashion. They don’t collapse overnight or unravel in a single bad year.
What they tend to do instead is underperform quietly, year after year, while still appearing outwardly sensible.
Statements continue to land, withdrawals may continue, volatility appears contained and on the surface nothing can look obviously wrong.
Until later on, when it becomes clear that the portfolio hasn’t actually kept pace with the life it was meant to support and the damage starts to show.
Income that once felt ok begins to feel tighter than expected, and flexibility that was assumed to be there has quietly eroded because of a long stretch of mediocrity that went unquestioned.
Rethinking Risk Profiling
This is where risk profiling and the way it is used across much of the advice industry deserves closer scrutiny.
Large advice networks, some with hundreds and in certain cases thousands of advisers, rely heavily on standardised risk questionnaires and centrally approved portfolio models.
And it isn’t because they produce better long-term outcomes. It’s because they keep advice delivery consistent, auditable and defensible across large organisations.
Even I understand that from a compliance perspective the approach makes perfect sense. But from a real lifetime outcome perspective it often doesn’t.
Risk questionnaires are designed to measure emotional tolerance to volatility, not whether a portfolio has a realistic chance of sustaining purchasing power over multiple decades while funding withdrawals.
The industry ends up optimising for comfort and uniformity because those things are easier to evidence, even when doing so quietly increases long term risk.
What the Data Shows
Last week I also said we would get to the data. And when we look at the data the issue becomes much clearer.
Using Dimensional’s long-term evidence, the FTSE World Government Bond Index delivered an annualised return of 2.5% over the 20-year period from 2004 to 31 December 2024.
Over the same period, average inflation (again using Dimensional’s compiled data) ran at around 3.7% per annum.
In simple terms, that means the bond component of a traditional 60/40 portfolio was losing roughly 1.2% per year in real terms, before allowing for fund and platform costs, and adviser fees.
In reality, the negative drag was probably closer to 2.2% per year.
And that’s also before you factor in the real world cost pressures we actually feel, which run a lot higher than headline inflation figures suggest.
That 40% allocation isn’t just defensive, it has been a persistent drag on purchasing power, quietly compounding in the wrong direction year after year.
Volatility Risk vs. Lifetime Risk
Over time, that negative compounding becomes deeply damaging. Maybe not in a way that draws attention early on, but in a way that steadily reshapes what the portfolio can ultimately support.
This is why the distinction between volatility risk and lifetime risk matters so much. Volatility risk is emotional and visible, whereas lifetime risk is structural and cumulative. One feels uncomfortable in the short term, and the other quietly reshapes the future.
A Standing Offer
If you’d like to see the underlying Dimensional data in full, I’m very happy to share the data book so you can review the evidence for yourself, in context, rather than relying on my summary.
And if any of the mails I’ve sent over the last few weeks have prompted questions about how your own portfolio has been constructed — particularly the balance between comfort today and endurance over the decades ahead — I’m always happy to have a private, non cost conversation to sense check things.
Not a review, and certainly not a commitment to change anything, just an opportunity to kick the tyres properly and make sure the assumptions holding everything together are still doing their job.
That’s often all that’s needed to bring things back into good order.
So, feel free to book a consultation using the link below, or simply reply DATA and we’ll send you the password protected PDF book directly by email.
16 January 2026.
