Question about TFA Casa

I don't quite understand the question. The unit measures the humidity exactly where the sensor is, i.e. indoors where the unit hangs, outdoors where the sensor is placed. Normally, the humidity in a room evens out evenly over time. Please explain your question. Thank you.

Anonymus is absolutely right, but the device runs reliably, but the measurement quality is quite different with all devices for measuring humidity, so the measured result is more of a trend measurement, or very relative:-)