Wann ein Arc Map sinnvoll ist
Your data describes movement between places
Flights, shipping lanes, trade between countries, migration, submarine cables. If every row has a start and an end, an arc map is the natural picture.
The connections matter more than the places
A reader should see which hubs are busiest and which regions are linked at all. Arcs make hubs and gaps obvious in a way a table of pairs never will.
You have routes in several groups
A filter control lets a viewer isolate one group, such as one airline or one trade bloc, so a crowded map becomes a set of readable ones.
Routes cross the Pacific or the dateline
Arcs wrap correctly across the antimeridian, so a Tokyo to Los Angeles route draws as one curve rather than a line streaking across the whole map.