What does the saying, "from shirtsleeves to shirtsleeves in 3 generations" mean??

The universal cultural proverb that says “shirtsleeves to shirt sleeves in three generations,” is as old as writing itself. And when I say universal, I mean that it appears in every culture I have studied. Clogs to clogs, kimono to kimono, rice paddy to rice paddy, shirtsleeves to shirt sleeves. And it is a proverb that describes human behavior in terms of creating long-term families as failure.

The theory of the proverb is that the first generation starts off in a rice paddy, meaning two people with an affinity for one another come together and create a financial fortune. They usually do it without making significant changes to their values, customs or lifestyle. The second generation moves to the city, puts on beautiful clothes, joins the opera board, runs big organizations, and the fortune plateaus. The third generation, with no experience of work, consumes the financial fortune, and the fourth generation goes back in the rice paddy. This is the classic formulation of the shirtsleeves proverb, which is as true today as it has been throughout evolved human history