Why do you believe that those two processes are in any way analogous?
Hunger is an explicit suite of hormonal control-system signals (leptin + ghrelin) evolved as an "instinct" to direct food motivation toward medium-term calorie caching in a seasonal feast-or-famine environment. You get "more hungry than you need" because your body is actively/intentionally trying to acquire "extra" calories to use to build fat stores.
Tiredness isn't an intentional conscious signal; it's rather the experiential qualia of a direct physiological problem — the gradual degradation of the brain's ability to function. Well-restedness is just the feeling of not being tired — of not having the inflammatory processes, brain fog, confusion, etc. that stem from said brain-function degradation. Sleep clearly rewinds this degradative process; getting little sleep results in impaired recovery. People (when not being woken up by an alarm) tend to sleep until the degradation is fully fixed, however long that takes. People who have harmed their brain in other ways — e.g. with alcohol, with hypoxia, with a concussion, etc. — take longer to naturally awaken from sleep, because their brain is recovering from a deeper state of degradation.
I'm not claiming anything here about the mechanism by which sleep enables recovery from the gradual brain-function degradation caused by being awake for a long time; but it's pretty clear that sleep does have that effect.
Hunger is an explicit suite of hormonal control-system signals (leptin + ghrelin) evolved as an "instinct" to direct food motivation toward medium-term calorie caching in a seasonal feast-or-famine environment. You get "more hungry than you need" because your body is actively/intentionally trying to acquire "extra" calories to use to build fat stores.
Tiredness isn't an intentional conscious signal; it's rather the experiential qualia of a direct physiological problem — the gradual degradation of the brain's ability to function. Well-restedness is just the feeling of not being tired — of not having the inflammatory processes, brain fog, confusion, etc. that stem from said brain-function degradation. Sleep clearly rewinds this degradative process; getting little sleep results in impaired recovery. People (when not being woken up by an alarm) tend to sleep until the degradation is fully fixed, however long that takes. People who have harmed their brain in other ways — e.g. with alcohol, with hypoxia, with a concussion, etc. — take longer to naturally awaken from sleep, because their brain is recovering from a deeper state of degradation.
I'm not claiming anything here about the mechanism by which sleep enables recovery from the gradual brain-function degradation caused by being awake for a long time; but it's pretty clear that sleep does have that effect.