Task Success Rate

Task success rate is the share of participants who successfully complete a specific, defined task, for example opening an account or finding and changing a delivery address. It is the most basic usability metric, and often the most decision-useful, because it ties directly to whether a journey works.

To be meaningful, success has to be defined in advance and applied consistently. A clear pass or fail criterion per task makes results comparable across participants, across cohorts, and across design iterations.

Success rate on its own tells you that a journey is hard, not why. Pairing it with behavioural detail, where people hesitated, backtracked, or showed frustration, turns a number into a fix.

OpenScouter reports task success at the cohort level, including how it differs for more sensitive cohorts, and pairs it with the behavioural evidence that explains the gaps. You can also iterate until success across profiles plateaus.