I often sleep more than 8.5hrs and I think there might be more here than meets the eye. For one thing I think if you sleep longer you're more likely to wake up

I often sleep more than 8.5hrs and I think there might be more here than meets the eye. For one thing I think if you sleep longer you're more likely to wake up dehydrated which makes you feel the sleep didn't do you well. You can avoid this by chugging water when you wake or by drinking water during the night. Also I think folks with allergies can feel worse if they sleep longer, if they're breathing more dust from pillows etc.