Originally Posted by
Viajero
Gardyloo is right. I'd also add the cost of buying an extra [unwanted] continent in some cases. For me buying an OWE ex-Africa means paying for a DONE5/6 where a DONE4/5 would do if bought elsewhere.
I've been planning an RTW itinerary where significant travel is in Europe, Asia Australia and New Zealand, with CAI, ATH, HKG, AKL, SYD, AYQ, PER and CNS being the cities of interest. So far, the options I have end up wasting North America/South America (OWE) or Africa (Circle Trip Explorer) but the continent count is the same.