Why do some people start a family business with relatives only to end up turning against each other?

And in the southern regions, family businesses—even after several generations—keep clear accounts and even grow bigger?
Today, let’s talk about the true meaning of the word "family." Over a thousand years ago, southerners ventured into Southeast Asia, braved the ocean, and explored deep mountains. They truly entrusted their lives to each other. If at that moment, the second uncle was lazy or the eldest brother kept secrets, the entire family might not survive that winter.
Therefore, in the memories of southern people, there is a very strict rule: outsiders can help you fend off danger, but internally, we must settle the accounts thoroughly.
Why are we not afraid of relatives stealing money? Because we have three unspoken rules:
First, relatives are just your ticket to entry; your skills are your seat number. In Guangdong, those without merit can’t even keep their place in the family tree or their livelihood.
Second, say the tough words at the tea table first. Many people are afraid to talk about money, but we believe that avoiding money is morally wrong. Before sharing dividends, we first discuss how to part ways clearly, so that when drinking together, everyone can genuinely smile.
Third, profit and righteousness coexist, but righteousness must not break the law. We use blood ties to eliminate suspicion, but we also guard the long-term with extremely cold rules. Mediocre relationships die when there’s no clear boundary, but high-quality relationships thrive because of well-defined limits.
Many people fear that too much emotion can suppress strength, but Guangdong people cultivate the idea that family ties should not be broken unless the heart is willing. Since everyone is just passing through, settling the accounts clearly keeps the heart unburdened. Do you understand this set of business principles?