⚖️Why Lotteries Return Only Half of Your Bet and the Stock Market Works Differently
Betting vs. Investing: Why Math Holds the Bank
It's Friday evening, you have an extra 500 Kč in your account, and a clear idea in your head: "If this works out, I'm set." You bet 200 Kč on the Eurojackpot, scatter 300 Kč across three football matches where you know the outcome. Your finger hovers over the "bet" button, and a pleasant cocktail of dopamine and tension spreads through your body.
By Sunday evening, the scenario is usually the same — from five hundred, you're left with zero because an underdog equalized with a penalty in stoppage time. And the feeling that next time it must work. Almost everyone knows this moment. And it's not about intelligence or bad luck. It's about one single variable that no one shows you in advertisements: expected value.
What is Expected Value (and Why It Decides Everything)
Expected value (EV) is simple: you take each possible outcome, multiply it by the probability of it occurring, and sum it up. It's the average result if you found yourself in the same situation a thousand times.
Imagine a fair coin and a 100 Kč bet: 50% chance to win 100 Kč, 50% chance to lose 100 Kč. EV = 0. A zero-sum game — in the long run, you're even.
The problem is that almost no gambling game is a fair coin. And here's where the interesting part begins.
A Tale of Two Thousand: Jakub vs. Martin
Let's imagine two friends. Both have 2,000 Kč free each month, both want to grow their money — but they approach it differently.
Jakub trusts his sports knowledge. Every month, he divides two thousand into smaller bets. Sometimes he wins, sometimes he loses, and when he hits 4,000 Kč, he celebrates with friends as proof that "he has a knack for it." But Jakub doesn't keep an exact ledger. If he did, he would find that over three years, he invested a total of 72,000 Kč in bets, but only sent back approximately 41,000 Kč to his account. The difference disappeared as a tax for the illusion of quick wealth.
Martin chose a more boring path. He sends the same two thousand each month via standing order into a diversified portfolio mirroring the global market. No weekend dopamine rides — he hardly looks at the portfolio. Over three years, he also invested 72,000 Kč and experienced periods when markets fell and his portfolio was temporarily in the red (which wasn't easy psychologically). But that's not a promise of anything — just an illustration of the principle that Martin plays a game where math works for him in the long run, while Jakub plays a game where it's set against him.
The difference between them isn't "luck." It's in the expected value.
Lottery: The Math That Plays Against You
The numbers for lotteries like Eurojackpot are publicly known and unpleasantly clear. Of every hundred bet, approximately only around 50% returns to players in the long run. The rest goes to other winnings, operations, taxes, and the operator's margin.
Translate this into EV: every 100 Kč bet has an expected value of approximately 50 Kč. Not because you're unlucky — but because the game is mathematically set up this way. If you kept betting indefinitely, the law of large numbers would inexorably pull you towards that fifty.
Sure, the jackpot can be huge. But the probability of the main win in these games is in the order of one in tens to hundreds of millions. For perspective: it's similar to hitting one specific blade of grass with your eyes closed on the area of dozens of football fields.
Sports Betting: The Illusion of Control
Sports betting is more insidious because it creates a sense of skill. "I watch football, I have information." But the bookmaker builds its margin into every odds — for regular matches, it ranges from 5 to 12%.
Let's illustrate this specifically: if two teams had perfectly equal chances (50/50), the fair odds would be 2.00 for both. The bookmaker, however, might list 1.85 for both — and in that difference is its margin. Practically, it means that even if you bet perfectly according to actual probabilities, the margin pushes you into negative EV.
That's why most bettors are long-term in the red — not because of one unlucky Sunday, but because they play a game where the average result is pre-set against them. And the more tickets and "accumulators" (combinations of multiple matches), the more the margin multiplies. Ten matches on one ticket look like ten chances — in reality, it's ten margins stacked on top of each other.
Stock Market: A Different Game at a Different Table
And now the crucial difference. Lotteries and bets are zero or negative-sum games — a fixed pot of money is divided among players and the house, and the house always takes a cut.
The stock market is a positive-sum game. Companies actually produce, sell, innovate, pay dividends, and grow. When you hold a stock, you're not buying a ticket or a bet — you own a piece of a business that creates new value. The pie grows over time, instead of just being redistributed.
Historically, broad stock markets have had positive average annual returns in the long run — in the order of single to low double digits when accounting for reinvested dividends and longer periods.
But beware, three important caveats:
- It's not a certainty. Markets fluctuate, declines of tens of percent have historically occurred.
- It's not quick. Positive EV manifests over years, not weekends.
- Past performance is no guarantee of future results. Historical data describe what was — not what will be.
Data Comparison in One Place
| Game | Who Creates Value | Expected Value | Horizon |
|---|---|---|---|
| Lottery | nobody (just redistribution) | strongly negative (return ~50%) | moment |
| Sports Betting | nobody (house margin) | negative (bookmaker's margin) | moment |
| Broad Stock Market | companies (growth, dividends) | historically positive, with risk | years |
Practical Framework: How to Move to the Right Side of the Table
Here's what you can take away today:
- Divide your money into two piles. "Entertainment budget" (feel free to bet, but treat it as the price for adrenaline, not an investment) and "growth budget" (money that should work). Treat the entertainment envelope as an amount you can lose entirely without hurting your budget.
- Calculate your annual ticket spending. Betting 500 Kč weekly? That's approximately 26,000 Kč annually, where the average result is pre-set negative. Write it down on paper — numbers hurt more than feelings.
- Set rules in advance. How much you set aside monthly, into what, how long you'll leave it. Rules written in calm protect you from decisions made in affect.
- Diversify. One stock is still a bet on one horse. Spreading across more companies and sectors reduces the risk of being sunk by a single event.
- Measure the horizon in years, not days. Positive EV needs time to manifest. Those who panic at every drop act like bettors, even if they hold stocks.
What to Take Away
- Know the game you're playing. Lotteries and bets have negative expected value — in the long run, you lose by principle. That's a fact, not an opinion.
- Investing is not certainty or speed — it's a positive-sum game with historically positive EV, but with real risk and fluctuation.
- Separate entertainment from strategy. Want adrenaline? Consciously allocate a small budget for it. Want your money to work? Build it on rules and diversification.
- Start by calculating your annual ticket spending and compare where that same amount would have EV on your side.
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- EV 36.1 as of 2026-05-31
The 0–100 figure is a descriptive QMA composite score. Score methodology
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Create a free accountContent created by AI in collaboration with Jaroslav Vojtášek. Not investment advice. The author may hold the stocks mentioned. Investing involves risk of loss.
Operator: Jaroslav Vojtášek, Company ID (IČO) 48783447.