Do you think it is wise that 24 year olds should get marry while working for a basic wage and may have to live in the same house with the guy's parents for the first year of marriage? Do you think it's a correct move? Mind you both parties are of a common understanding.
"Therefore a man shall leave his father and mother and be joined to his wife, and they shall become one flesh" (Genesis 2:24).
In many cultures both in the past and through today, it is common for several generations to live in the same house. In the United States we haven't needed such because of well paying jobs and reasonable housing. However, things are beginning to shift.
Leaving is not so much a matter of moving to a separate home as it is the independence each family has in making its own decisions. Sadly, many parents have a hard time adjusting to seeing their children as adults and treating them as such. Therefore, much depends on the people involved.