Humans are a social sort. We thrive and have become the dominant apex species largely because of our ability to socialise, combined with our capacity for communication.
A large part of socialisation in our close-knit groups involves the ability to ask others for favours. We ask favours from friends, colleagues, family members, government officials and so on. In fact, we build up a "favour bank" with those around us.
Many people think they should merely check on someone with daily greetings—saying hi or asking how they are—so that they can then spring a surprise request on someone a few days later.
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