Let's say you're an airline executive focused on maximizing profit. Do you aim to fill every seat on each flight? Or do you raise fares, knowing that a few seats -- or even more -- might go empty.
For most airlines, the emphasis is on the latter. The goal, almost always, is to make the most money. If that means not every seat is taken, so be it.
"You can make it very simple," said Chuck Schubert, vice president of network planning for American Airlines. "If I could sell all my tickets for $10, I am certain I could fill the plane. But I'm also certain I could not make money. It's about balancing the load factor of the plane with the yields, or what people are willing to pay.