The risk-reward ratio compares how much you will lose if a trade fails against how much you will make if it works. Risk $100 to make $200 and your ratio is 1:2. It sounds basic, but it is the single number that decides whether a strategy survives contact with a losing streak.
Why win rate lies
Traders obsess over win rate - the percentage of trades that profit. But win rate is meaningless without the ratio beside it. Win 70% of trades risking $100 to make $30, and a normal cold streak wipes out months of gains. Win 40% of trades risking $100 to make $300, and you are highly profitable. The math, not the hit rate, is what pays. We unpack the pairing in win rate vs. profit factor.
Expectancy: the number that matters
Combine the two and you get expectancy - the average outcome per trade. A positive expectancy means that, over enough trades, the edge compounds; a negative one means the account bleeds no matter how many individual wins feel good. This is why a defined exit is non-negotiable: without a known loss, you cannot compute the ratio, and without the ratio, you are not trading a system - you are gambling with extra steps.
You do not need to be right often. You need your winners to outweigh your losers - reliably.
Making the ratio mechanical
The ratio only works if it is enforced every time. That means a hard stop and a target set before entry, and the discipline to honor both when the trade goes against you - the exact moment humans cave. Pairing a sane ratio with strict position sizing is the difference between a rough month and a blown account.