What Is the ‘Luck’ Percentage Displayed by Mining Pools, and What Does It Indicate?
The 'luck' percentage is a metric that compares the actual number of shares submitted by the pool to find a block versus the statistically expected number of shares. A luck percentage above 100% indicates 'bad luck' (more shares than expected were needed).
A percentage below 100% indicates 'good luck' (fewer shares were needed). It is a measure of the pool's variance.