The Cove Relaxation Index (CRI) uses heart rate, head motion, body motion and other data to visualize how you relaxed during a session. Sometimes, Cove does not capture all necessary information to create this visualization.
There are several factors which can lead to incomplete data:
Hair blocking the heart rate sensor
Distance between the sensor and the skin
Too much excessive motion
When no CRI is generated, the Cove app will include additional information. Just tap the session in the History tab to learn more about why CRI was not created.