Once we sleep, the brain sweeps away the buildup of adenosine. When we wake in the morning, the accumulation of sleep pressure starts anew.
However, if you are regularly not achieving the recommended 8 hours of sleep, the full amount of adenosine will not be removed from the brain. Leftover adenosine causes us to consume more caffeine in the morning, starting the process all over again. Therefore if you are looking to cut down on your caffeine intake, achieving a higher quality and quantity of sleep can do the trick.