The gradual rise of worldwide mega-airports stemmed from the realisation that not every point on a map could be connected directly to every other.
Whether this was due to insufficient capacity and demand or the fact that aircraft do not have the range to link every city worldwide non-stop. In addition, many point-to-point markets also had limited demand rendering direct services as unviable. The solution was solved through a ‘hub and spoke’ model that channels customers through a central location enabling flights (or spokes) to be fed from a multitude of destinations.