Trade twice a week at ordinary costs and you begin every year about 19% behind. Not because you are undisciplined, not because you lack a system — because of arithmetic that applies before you have made a single decision, and applies identically to your best year and your worst.
The argument against trading is usually made in the language of psychology: greed, fear, discipline. That argument is true and it is the weaker one. The stronger one fits on an envelope.
What frequency costs, before anything else
Spread plus commission, compounded across a year of round trips
| How often you trade | Round trips a year | At 0.1% per trip | At 0.2% | At 0.4% |
|---|---|---|---|---|
| Once a month | 12 | 1.2% | 2.4% | 4.7% |
| Once a week | 52 | 5.1% | 9.9% | 18.8% |
| Twice a week | 104 | 9.9% | 18.8% | 34.1% |
| Every trading day | 252 | 22.3% | 39.6% | 63.6% |
Read the fourth row again. A day trader at ordinary retail costs must generate about 40% of gross return a year to break even. The market's long-run return is a fraction of that. The strategy is not competing with the market — it is competing with the market plus a handicap larger than the market's entire return.
And this is the charitable version. It assumes every trade executes at the quoted price, no slippage on the ones that matter, and that the spread does not widen precisely when you most want out. It usually does.
Frequency is the only variable in investing that reliably costs money and reliably feels like effort.
The tax you pay for being busy
Same return, same rate — only the timing differs
A gain you do not realise is an interest-free loan from the tax authority, and it compounds. Take an 8% annual return at a 28% rate on gains:
| Horizon | Realising every year | Paying once at the end | Difference |
|---|---|---|---|
| 10 years | 1.75× | 1.83× | +4.8% |
| 20 years | 3.06× | 3.64× | +18.6% |
| 30 years | 5.37× | 7.53× | +40.2% |
Forty per cent more final wealth, from a single behavioural difference: leaving it alone. Nothing was analysed better. No stock was picked more cleverly. The same return was earned and the tax was simply paid later.
Combine the two hurdles and the picture is bleak before skill enters the room. The weekly trader loses roughly a tenth of capital to friction each year and surrenders the deferral benefit permanently. Skill has to cover both before it shows up as a single euro of outperformance.
You have to be right twice, about other people
Buy a business and hold it, and you need one thing to be true: the company earns more over time. You do not need anyone to agree with you, and you do not need a date. Being right slowly still pays.
Trade it, and you need three things: to be right about the company, to be right about when other people will come to the same conclusion, and to be right again about when to leave. The second of those is not a statement about a business at all — it is a forecast of other people's future opinions, and there is no financial statement anywhere that contains that information.
Every large study of actual brokerage records tells the same story, and the studies are not the interesting part — the mechanism is. Trading is one of the few activities where effort is negatively correlated with outcome. Working harder means trading more, and trading more means paying the table above more times. In almost every other field, more work is more result. Here it is the reverse, which is exactly why intelligent people find it so hard to accept.
Somebody is making money. It is not you.
Trading profits are real. They accrue to the people on the other side of the spread: market makers with costs near zero, wholesale funding, and holding periods measured in seconds. That is a genuine business, and it is not the business in the advertisement.
The useful question when someone shows you a trading strategy is not whether it worked. It is: at what cost per round trip does this stop working, and where do I sit relative to that number? Most published strategies do not survive a 0.2% round trip, which is why the backtests almost never include one.
What the arithmetic recommends instead
- Fewer decisions, better researched. Twelve round trips a year at 0.2% costs 2.4%. Two costs 0.4%. The entire handicap is a choice about frequency, and it is the one variable fully under your control.
- Hold long enough for the business to matter. Over a week, a share price is a poll. Over a decade, it is a scorecard. Only one of those is something you can research.
- Let the tax compound for you. A position you do not sell is a position whose gains keep working. That is not a loophole, it is the default, and being busy is what gives it up.
- Judge yourself on the decision, not the quarter. If the reasoning was sound and the facts have not changed, a price move is not new information. Reacting to it is trading, whatever you call it.
Two businesses built to be owned rather than traded — one of them by the man who made the argument famous.
What to do with this on Monday
Count your round trips over the last twelve months — your broker will tell you — and find yourself in the first table. That percentage is what you paid for the privilege of being active, and it came out before any judgement of yours was tested.
Then ask what it bought. If the answer is that you would have done roughly as well leaving the portfolio alone, you have just measured the most expensive habit in personal finance, and you are one decision away from stopping.
Frequently asked
Why do most traders lose money?
Because they start each year behind. At an ordinary round-trip cost of about 0.2% in spread and commission, trading twice a week means roughly 19% of capital consumed by friction before a single decision is judged. Add tax on every realised gain and you need to be substantially better than the market simply to match it.
Isn't trading just investing with a shorter horizon?
No, and this is the part that gets skipped. Buying a business means you profit if it does well. Trading means you profit only if someone else changes their mind in your favour, inside your window. The first is a claim about a company. The second is a claim about other people's future opinions — a much harder thing to be right about repeatedly.
What about tax? Does frequent trading really cost that much?
Over long periods, yes. At an 8% return and a 28% rate, realising your gains every year turns €1 into about €5.37 over thirty years; leaving the position alone and paying once at the end turns it into about €7.53. That is a 40% difference in final wealth, produced by nothing except when the tax was paid.
Can anyone make money trading?
Yes — the people on the other side of the spread, at institutions with costs near zero, borrowing at wholesale rates and holding positions for seconds. That business is real and it is not the business being sold to retail investors. If the strategy you are being shown requires a private investor to overcome a 19% annual handicap, the person teaching it has found a better business than the one they are describing.