I had a friend whose legal name here in Canada was Juliana Juliana. She came from Indonesia and didn't have a family name. They told her she needed to have two names for her visa application so she just doubled up her given name.
Mongolians use their Father's name as their surname, but they write it first. So if my name would be Brad's Josh. While you may think that they should just write it backwards, that isn't how they write it, and they shouldn't be required to translate their names for our systems necessarily.
The point he is making is that people make one assumption or the other, deepending on the culture in which they live, when actually it varies.
In the western world, we assume that someone's family name is their last name.
In countries such as Korea, people assume that someone's family name is their first name.
Either assumption can be wrong if you're dealing with international customers. Some people might not even have a family name.
++ People's first name is their "family name".
++ People have first names and last names.