Shot quality

Shot quality refers to models and metrics that grade the difficulty or danger of an individual scoring attempt, rather than simply counting attempts or makes. The concept spans several sports: soccer and hockey's expected goals models and basketball shot-location analysis all try to answer the same underlying question, how likely was this particular shot to succeed, given where and how it was taken.

Shot-quality models typically use factors such as distance and angle to the goal or basket, the type of shot, headed, one-timer, contested jumper, and the defensive pressure at the moment of the attempt, trained against large samples of historical shots with known outcomes. This is distinct from shot-volume metrics like hockey's corsi and fenwick, which count attempts without judging how dangerous each one was; a team can generate many low-quality shots or fewer high-quality ones, and shot-quality models are what distinguish the two patterns.

Teams and analysts use shot-quality data to evaluate finishing skill separately from chance creation, and to explain why a team's results diverge from its shot totals. The main pitfall is comparing shot-quality figures across data providers as if they were interchangeable: different providers train their models on different shot samples and features, so the same shot can receive a meaningfully different quality score depending on the source.