People say it as a sugar-coated way to express "if you're unhappy, it's because of a character flaw, so you should internalize your frustration, not express it

People say it as a sugar-coated way to express "if you're unhappy, it's because of a character flaw, so you should internalize your frustration, not express it to other people, deal with it privately, and definitely don't politicize it."