The earliest words come from "Jin Shu·Yang Hu Biography", other sources: Southern Song Dynasty poet Xin Qiji's poem "Congratulations to the Bridegroom·Use the previous rhyme and then rhyme": sighing about life, unsatisfactory things, ninety-nine times out of ten. After Xin Qiji, there was a poem by Fang Yue from the Song Dynasty: Things often go wrong as you wish, but you can always tell people the same thing. ("Commander Biezicai"). The couplet "Unsatisfactory things often happen, but they are the same as the poet", which has been common in operas and novels since the Yuan and Ming dynasties, is based on Fang Yue's poem.

The popular explanation is that it is impossible for a person's life to be smooth sailing and everything goes as planned. There are always some ups and downs. Suffering, this way people will live better. There are many things you encounter in your life, and they are all unsatisfactory. We are encouraged to work hard.

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The Southern Song Dynasty poet Xin Qiji (1140-1207 AD) wrote "Congratulations to the Bridegroom·Use the Preface Rhyme and Re-Fu": Sighing about the unsatisfactory things in life is a common occurrence.

Fang Yue, a Song Dynasty poet, wrote: Things often go wrong as you wish, but you can always tell people the same thing. I know that Jingmen is a talented person, and I dream of galloping with iron horses to fight in the south of the city.

Fang Yue (1199-1262), whose courtesy name was Jushan and whose name was Qiuya, was from Qimen and was known as "Mr. Qiuya's Small Draft". In the late Southern Song Dynasty, his poetry was very famous, almost as good as Liu Kezhuang's. It seems that he originally started from the Jiangxi School, and was later greatly influenced by Yang Wanli and Fan Chengda. He has the habit of organizing allusions and idioms into novel parallels. For example, the couplet "Unsatisfactory things often happen all the time, but they are the same as the speaker" which has been common in operas and novels since the Yuan and Ming Dynasties. This is his poem.

--Qian Zhongshu's "Selected Notes on Song Poems"

Reference material: Nine out of ten things in life are unsatisfactory - Baidu Encyclopedia