A health and fitness tracker that cannot be worn during a common health and fitness activity seems highly problematic as a form factor, especially since competing form factors do not have this problem.
Not necessarily common, but I imagine most form factors would have issues with _some_ activities. I have a fitness watch that I don't like wearing when rock climbing. A ring also isn't suitable, but an armband worn further up would be.
It’s a little intellectually disingenuous to compare something you don’t like wearing during a niche sub categorical activity to a category of tracker you CANNOT wear during a categorical activity.