If compound interest is the 'eighth wonder' of the world, what's the ninth?

‍I've always loved the idea of compound interest. Once capital is invested, even just by sitting there, value accrues by what's often called 'the eighth wonder of the world': he who understands it, earns it; he who doesn't, pays it.

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It's actually very similar in product management, where there's a fundamental, under-leveraged truth, one often overlooked under the weight of 'busy work' or building the latest feature, yet arguably the one that delivers the greatest benefit of all. Compounding. The art of creating accruing benefits of stability, performance, resilience and impact, because your product or system simply shows up more of the time, falls over less, and bounces back quicker and more gracefully when it does fail. That's compounding, right there.

‍So how do we 'compound', and realise these benefits for the products we lead? Like many things in product, it can flow from a framework, and a framework can provide the scaffolding your product needs to win in an ever more complex and morphing world. Let's compound.

‍The framework I've developed in this area, applied to products I've led across four different sectors, is one I call the Four Fs.

‍I built this framework from watching priorities in product default to the 'highest profile thing', the 'noisiest thing', or the 'flavour of the moment'. All of this creates its own noise, and distorts what a product is primarily set up to do. (Bonus tip: leaning into your Product Vision in such moments is never a bad idea either, or even stress-testing it to check it still holds true). The cost is ignoring the baby elephant in the room, until it grows into the proverbial elephant in the room. I call that ‘inverse compounding’.

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1. Front Foot Forward

‍I've always liked Covey's maxim, 'start with the end in mind'. This F is similar, but different. It's the foundational F, and it asks for acceptance of two continuums: continual progress, and continual improvement. That's the very definition of compounding in product, moving forward deliberately rather than reactively, before the next fire forces your hand.

‍Once a team accepts and aligns with that principle, the art becomes unlocking the compounding benefit. That's where the other three Fs come in.

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2. Foresight Is Your Friend

‍This one's about thinking ahead, before you need to, or before events force you to. It's about being the devil's advocate to your own product's set-up, build and architecture, or getting others to play that role for you, if necessary.

‍ What you're trying to baseline are three things: what could go wrong, how likely is each thing to go wrong, and what other dependencies and wider considerations affect your product performing well under pressure, peak load, unexpected events, macro factors, or attacks and threats from outside.

‍Use these to baseline what comes next.

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3. Fire-Risk Prevention

‍This is the one I've seen too often overlooked, yet it's often the biggest opportunity in products at scale. The dedication and precision to take what's found in Foresight and counter those risks accordingly, so the ‘elephant’ never fully grows in the first place. Modernisation, patching, refactoring, all components of this F. But so too are more nuanced plays: test and learn rather than fail and burn, and genuinely mapping your true dependencies, have you really mapped every endpoint?

‍This is the richest opportunity in the Four Fs, and it sets the stage for the final one.

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4. Forearmed

‍We all like to sleep at night, don't we? Product leaders, engineering leaders, teams building and running products, or supporting them in live.

‍Forearmed is more than the sum of the other three Fs, it's the defining principle. It's taking what they've developed and asking, honestly: does this range of optimisations, enhancements and preventative plays really give our users the most performant, reliable product we can provide? Or does it still fall short? If it falls short, return to the first F and work forward again. Your users, your business, and general karma will thank you for it.

‍Four Fs, four principles, four ways to build products for tomorrow, not just today. That's the ninth wonder: not compound interest, but compounding capability, deliberately built, ‘F by F’.

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>So what's your take? How do you apply foresight and forearmed thinking to your own products? And what's the cost of not acting, if you don't?

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> Searching for more ways to compound the benefits in your product? More in the book, ‘Product Truths: Five Principles for Building Products That Work at Scale’. Available at all major digital bookstores (Amazon Kindle, Kobo, Apple Books):
Available at: www.Books2read.com/producttruths

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The Four Fs of compounding products

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Your next incident won't define your system's fortunes. Your work before the storm will

One question I'm often asked: 'how do we create performant and resilient systems, at scale?' It is a sound question to ask.

But behind this query, there often sits an uncomfortable truth. Many large-scale systems morph and iterate over time, often without embedding the 'preventative and performative' elements that ensure high levels of service quality, availability and experience for the end user. This is a material risk to large-scale systems today, and systems at scale can literally live or die by it.

So important, then, that the 'real world readiness' of the system to react, adapt and bounce back at scale is built into its very core, by design.

This is why I developed the 'Three Ps' Framework, for performant systems. It's the set of guardrails and 'silent scaffolding' I apply to my products at scale, to not only ensure high levels of performance and 'non-functional' robustness when the system is live and running, but also to power its recovery and bounce-back when it goes down. All systems experience such moments, at some point or other. Best, then, to be prepared. Enter the Three Ps.

The Three Ps of Performant Systems

Plan: map out blind spots, the risk areas, the unhappy paths, and run through the key 'What If?' scenarios, to stress test your system in advance. This 'P' serves a cunning twin purpose: it helps prevent many problems from hitting the system in the first place, whilst also providing the fuel for a further 'P' to be built and readied in advance: Prepare.

Prepare: for the worst, whilst always hoping for the best (the worst will often happen anyway, so best to be ready). Your disaster management and recovery systems, your runbooks, incident and escalation paths that need to play out in real time, need to be stress tested whilst the sun is shining, not once the storm itself arrives. They need to be documented, and easily accessible too, ready for those moments of truth when they hit.

Perform: the final 10% of how you act in the moments of crisis, or when the system is tested. Even this can be dry run or rehearsed (part of 'Prepare'), to build the crisis management muscles before they're ever even needed. It's like how fire crews don't just sit idle waiting to attend the next fire or incident, they train, they rehearse, they develop new smarts to counter emerging threats. So too with resilient systems at scale. The 90% readiness comes from the first two Ps; the remaining 10% comes from how your team performs in those moments of truth.

Over to you: how do you engineer your systems at scale to be highly performant in the 'usual' times, but able to react and recover when the system is under real world stress?

More Product Truths in the book, 'Product Truths: Five Principles for Building Products That Work at Scale'. Available at all major digital bookstores (Amazon Kindle, Kobo, Apple Books): https://books2read.com/producttruths.

The Three Ps of Performant Systems: Copyright Ian Finn, 2026