To
@maquiscat's point, from your article:
Despite Chick-fil-A’s poor showing in the speed portion of the study, the chain tied with Carl’s Jr. to score the highest in customer satisfaction with their drive-thru experience, which takes into account staff friendliness as well as customer expectations about how quickly they expect to receive their food.
Strictly from observation, I would bet CFA having a slower line is
heavily due to them always having a line of cars. People love them some chik fil a, so, you'll be stuck behind them, but taco bell? Who is in front of you?