The user experiences a mismatch between their subjective feeling of sleep quality and what the Garmin Fenix 8 reports. Specifically, the watch fails to register longer periods of wakefulness. They also complain about inaccurate heart rate measurement during weight training.
I switched from an Apple Watch Ultra 2 to a Fenix 8 about six months ago, primarily because of the wealth of data and the battery life. Unfortunately, I'm becoming increasingly disillusioned with the data. For example, my subjective perception of sleep and what the watch displays are increasingly mismatched. If I felt like I had a great night, it tells me I had a bad night's sleep (and vice versa). Sometimes, longer periods of wakefulness aren't even registered. Other features, like the heart rate measurement, are also completely unsatisfactory. The measurement on the Fenix 8 is practically useless, especially during weight training. This morning, for instance, I did squats, and the watch then showed me what was essentially my resting heart rate (see image). Is it just me, or have other users had similar experiences? I'll probably switch back to Apple this fall. It was worth a try.