How a 60% Win Rate Still Lost Money — Why Expectancy Beats Win Rate

The strategy won 60% of the time and still posted a net loss. How?

Because the wins were small and the losses were large. Win rate tells only half the story — the other half is average P&L, and you need both to calculate expectancy. Winning 60% of 20 trades while posting a net loss maps precisely to this asymmetry.

When I first saw the backtest output, it looked strange. A 60% win rate instinctively reads as "good strategy."

But once you decompose the numbers, the answer is obvious.

The Structural Imbalance — Small Wins × Big Losses

Average winning trade: $30–$50. Average losing trade: $100–$346. If you win 12 and lose 8 in a 20-trade sample, the math becomes 12 × $50 = $600 in profit versus 8 × $200 = $1,600 in losses. Win rate 60%, net P&L −$1,000.

It looks paradoxical, but it's a common real-world pattern. Strategies that exit at RSI reversals tend to book profits quickly — small and fast. Meanwhile, when a trend extends against the position, losses keep growing while the strategy waits for a reversal signal that takes longer to arrive. Wins are short. Losses are long.

Expectancy — the Real Metric

Here's how expectancy is calculated:

Expectancy = (Win rate × Average win) − (Loss rate × Average loss)

At 60% wins with $50 average win and $200 average loss:

Expectancy = 0.6 × 50 − 0.4 × 200 = 30 − 80 = −$50

Every trade has an expected value of negative $50. Twenty trades project to a $1,000 loss. That's exactly what the backtest produced.

Why Traders Obsess Over Win Rate

Psychology. "60% win rate" sounds great. "−$50 expectancy" sounds technical and uncomfortable. But expectancy is what actually drives the equity curve.

Some traders run the reverse: 30% win rate with an average win that's four times the average loss. Expectancy = 0.3 × 400 − 0.7 × 100 = 120 − 70 = +$50. They lose 7 out of 10 trades, but a single large winner offsets several small losers. Most trend-following strategies look like this.

Practical Checklist

Before evaluating a new strategy, calculate expectancy first.

• Don't just look at win rate — compare win rate × average win against loss rate × average loss
• Check whether one or two worst trades eat up the entire P&L in the backtest
• Confirm that the average R/R ratio is above 1.5:1

A 60% win rate strategy isn't automatically bad. But average win must exceed average loss. Conversely, a 20% win rate strategy can thrive if the average win is five times the average loss.

What matters is the combination of numbers — not any single metric.