Liu Gang came to Liu Ke's side after moving to the South. Before heading south, he knew the two kids were starting a business here.
He knew they were working very hard, sometimes just grabbing a quick bite to eat. Knowing this, Liu Gang felt reluctant to let them continue like this and opted for early retirement to take care of them.
Liu Gang never understood, even if a business could earn a lot of money, it shouldn't be at the cost of one's health.
Only after moving south did he realize that Liu Ke's business was really raking in money.
Time is literally money; besides supporting his son and daughter-in-law, Liu Gang also had to help in various ways.
Busy as he was, the business was indeed profitable. Only then did Liu Gang understand why his sons were reluctant to return to Capital City.
Initially, he worried that if the kids didn't return, the house in Capital City might end up in Liu Qiang's hands, which he was really unwilling to see happen.