Not sure if this is technically a bug but the advice page provides insights that I don’t think I should follow. For example, “to maximize deep sleep your duration should ideally be 4:41.” I have my goal set to 7 hours. It would be more helpful if it said “with your goal being __ hours, you’ve had the best deep sleep % when _____ occurs.” Additionally, my average bedtime is around midnight and so the advice of going to bed at 3am is also unhelpful.
This state has been achieved by us trying to really dodge any hints of providing any medical advice by a far far far.
What we are doing here is just being really a statistic provider and letting you draw your conclusions. I understand that the values you see look really weird, however that’s just because we have seen a similar pattern in your past data - that e.g. when you went to sleep around 3 AM, your deep sleep % was the biggest in your data.
You may not have enough data for this model to be meaningful however (in which case of course we shouldn’t really display these advices).
However it’s a very good point that we should take your goal into the equation.
If you go back a year, or “all,” you’ll get a more meaningful picture of better advice.
But yes, their advice should take into account your desired sleep quantity and perhaps when you wish to fall asleep.
Some sleep studies recommend a window between 10 PM to 2 AM as the ideal window for optimal benefit. Miss it and you’re out of luck. This applies to both night owls and morning larks. Lights out and under the covers, starting tracking after 10 and before 2. A kind of rule of thumb. I have a separate reminder in the Android reminder app and in a text to speech app warning me at 1:30 AM to wind down reading, work, viewing to be able to push the button before 2. Doesn’t mean I always listen, but I do my best.
Perhaps such studies of optimal fall asleep hour would help with better advice.
Another thing is that if you are sleep deprived and sleep for a short time, your deep sleep percentage rises because you fall into a deep sleep just from exhaustion. That should be discounted in advice, imho.