Master marketer and best-selling author Seth Godin says that companies that resist innovation are like brown cows—after a while, they all look the same. If you’ve seen one brown cow, you’ve seen every brown cow there is to see. You don’t notice them even when they’re standing on the side of the highway. They might as well be invisible. But when a purple cow comes on the scene, it stands out at once. You can’t take a brown cow and paint it purple, Godin explains. Purple cows are purple from the inside out—or they might be blue from the inside out, as in the case of JetBlue Airlines, a company that meets Godin’s criteria for excellence.