Thats a pretty complicated situation.I dont think there will ever be a solution to this issue.For instance,if we're talking about the country of your own birth,then Trezeguet wouldnt have played for France,Vieri wouldnt have played for Italy etc.Vieri for instance,has an Italian father,a french mother,and he was born in Australia.That effectivley makes him eligible for 3 countries.But yes,both these players became eligible for their respective countries because of their parents.
But what about someone who was born in Uganda,who has Chinese parents,and who lived his entire life in a country like Brazil,thus getting the nationality to that very country?On paper he becomes eligible for all 3 countries,and to be honest,he'd have the right to play for Brazil as he's lived his whole life there.but he wasnt born there,nor does he have Brazilian parents.
Reverse the situation,and what if someone was born in Brazil,has Chinese parents,but lived his entire life in Uganda?If he chooses to play for Brazil,fans wont exactly welcome him because he hasnt lived in the country at all,nor does he have Brazilian parents.
Its a loophole in FIFA regulations that can never be solved in manner that will make everyone happy IMO.