That is the gold standard for a fast-food drive-through, and McDonald's and its rivals have developed a science of sorts to try to meet it. Each year, the drive-through captures a little more of the fast-food industry's sales, so a smooth-running drive-through is a competitive advantage.
"People decide whether to come to your restaurant based on how long the drive-through line is," said R. Craig Coulter, chief scientist at HyperActive Technologies, a Pittsburgh-based restaurant software firm. Often, he said, "If there are seven cars in your line, they will go to your competitor."
