One of the most expensive mistakes in investing is to underestimate fees.

People hear 1% or 1.5% a year and think it sounds trivial. They imagine it’s a small cost of doing business. A minor detail. The sort of thing only obsessive people worry about.

That is a very expensive misunderstanding.

Because fees do not just reduce your returns once.

They reduce them every year.

And every pound lost in fees is not only gone today. It is also gone from every year of future compounding that pound could have enjoyed if it had stayed invested for you instead.

That is where the real damage lies.

A low-cost ETF may charge a tiny annual fee. A managed product or adviser-led portfolio may charge much more once you add up the layers: adviser fee, platform fee, underlying fund fees, trading costs, and all the other little nibbles that mysteriously appear.

Each one sounds tolerable on its own.

Together, they can do extraordinary damage.

Suppose you invest £5,000 for 30 years at 10% a year.

At that rate, you end up with roughly £87,000.

Now knock just 1% off that annual return, so instead of 10% you get 9%.

You finish with around £66,000.

That is roughly £21,000 gone.

And what changed? Not the market. Not your intelligence. Not your discipline. Just the annual drag of fees.

Increase that drag further, and the gap becomes uglier still.

This is one of the quietest truths in investing: a lot of people do not fail because they chose terrible investments. They fail because too much of their return leaked away before it ever had the chance to compound.

John Bogle, the founder of Vanguard, put it beautifully:“Every pound you pay in fees is a pound that doesn’t get to grow”

That line is worth remembering.

Because there are many things in investing you cannot control.

But you can control what you pay.

And because you can control it, low fees are one of the most reliable advantages available to an ordinary investor.

A lot of people go looking for sophisticated edges.

They imagine the answer must lie in some advanced strategy, specialist knowledge, or hidden opportunity.

Very often, the edge is much duller than that.

It is simply refusing to overpay.

That may not sound exciting.

But over a lifetime, it can make you vastly richer.

Thatis what this newsletter is about:

I’m not a financial adviser, and nothing I write is personal financial advice. But I am someone who has done this with real money, for real, over a long period of time — and I think that counts for something.

Every week I’ll share ideas, insights and practical guidance on how to manage your own investments — and do it better than most people who pay professionals to do it for them.

If you’re just getting started, my eBook — Make Yourself Rich — will give you everything you need to get set up, step by step. It takes a couple of hours to read, and by the end of it you’ll have a complete investment strategy you can put into action straight away.

And if you want to follow exactly what I’m investing in, why, and how it’s performing — including the individual stocks I hold alongside my core ETF portfolio — that’s what the paid subscription is for. More on that soon.