How did virgin america enter the airline industry despite the industry's notoriously low profitability?

The rivalry among the airlines made it easy for Virgin America to create a profit for themselves. They just offered a lower price than the other airlines with travelers that were traveling from major cities. They knew that the supplier power was strong, so this made it more affordable for them to do so. The lower prices diverted customers from using their cars or trains to travel instead of the airline. It was faster and more convenient.