Picture this: a trader closes 70% of their trades as winners. Sounds impressive. But every winner nets $200 and every loser costs $800. After 100 trades — 70 wins, 30 losses — the account sits at $14,000 gained and $24,000 lost. Net result: down $10,000. Win rate alone built exactly nothing.

This is the core tension in trading system design. Win rate measures how often you are right. Reward-to-risk ratio measures how much you make when right versus how much you lose when wrong. Neither number means anything without the other. Traders who fixate on one and ignore the other are flying with half an instrument panel.

CONCEPTExpectancy = (Win Rate × Avg Win) − (Loss Rate × Avg Loss). Positive expectancy is the only number that pays bills.
WARNINGA 90% win rate with a 1:10 risk-reward ratio produces a losing system. Do the arithmetic before trading live capital.
KEY IDEALower win rates are mathematically viable — provided the reward-to-risk ratio compensates with enough magnitude.

The relationship between these two variables forms a survival curve. A system with a 40% win rate requires at least a 1.5R reward-to-risk ratio to break even — before commissions. At 33% win rate, you need 2R minimum. At 25%, you need 3R. These are not suggestions. They are arithmetic constraints the market enforces without mercy.

Break-Even R:R Required by Win Rate4R3R2R1R20%33%50%67%80%1:1Win Rate

Trend-following systems historically run win rates between 35–45% but target 2R to 5R per trade. Mean-reversion systems often achieve 60–70% win rates with tighter 0.8R to 1.5R targets. Neither approach is superior — both can generate positive expected value when the parameters are internally consistent. The error is mixing a low-win-rate entry strategy with a small reward target, or cutting winners early while letting losers run — which destroys the risk-reward ratio the system was designed around.

Define your system's minimum acceptable expectancy before placing a single live trade. Then protect it — ruthlessly — through position sizing, hard stop discipline, and never moving a target closer once a trade is open.

Win rate is vanity. Expectancy is sanity. Build around the number that actually compounds.

This content is for educational purposes only and does not constitute financial product advice. Past performance is not indicative of future results. Profit Logic Ltd (ACN 688 669 936) accepts no responsibility for errors or omissions in this content or anywhere on this website. Always seek advice from a licensed financial adviser before making investment decisions.