it seems like sending a "good morning" or "good night" are overrated but they do have some important features,
like,
at the end of the day when you're shattered after a hectic day, you don't feel like doing anything, you're tired but can't sleep, then a sweet "good night" is like sleeps pill, it'll let your tension to go away and help you to sleep better for the very next day.
in the next morning while you're not feeling like waking up, a sweet "good morning" can cheer you up and can give you the energy to run for the rest of the day.
"good morning" and "good night" are just not formality, they are sign of care, they give you a sense of belonging that you're not alone, at least someone is there who cared about you.
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