Source or sensor

Ask what actually did the catching: which instrument, person, or system picked up the trace and passed it along. Check that it was running, calibrated, aimed at the right thing, and free of its own incentives.

Ask what actually did the catching: which instrument, person, or system picked up the trace and passed it along. Check that it was running, calibrated, aimed at the right thing, and free of its own incentives.

Example

In the satisfaction case, the sensor is the in-app popup that replaced the email survey. It only fires for people already inside the product, so the angriest customers, the ones who stopped logging in, never reach it.