In Third World countries they are based on criteria such as “what doesn't cost us, let's make it a party”. It is torture to see families that were once united battling over who gets the biggest or best slice of the cake, which then evaporates. Others, sole heirs, let the property whose parents built with sweat and tears deteriorate.
Perhaps, with first-world thinking, the conception of an inheritance is handled properly.
As I write, I was reminded of a nice film related to this topic, “The Last Gift” (2007).
Lawyers don't mind this.
I am not so sure. I think it comes down to family itself. I have seen some terrible outcomes here.