I've found that paying attention to the type people in the line matters as much as the number of items and the payment type. It sounds silly but I learned this

I've found that paying attention to the type people in the line matters as much as the number of items and the payment type. It sounds silly but I learned this from Apu on the Simpsons: “Season 5: “Homer and Apu” Original airdate in N.A.: 10-Feb-94 Apu and Marge wait at the back of the long line in the express lane. Apu: Mrs. Simpson, the express line is the fastest line not always. That old man up front, he is starved for attention. He will talk the cashier’s head off. Abe: {Ah, there’s an interesting story behind this nickel. In 1957, I remember it was, I got up in the morning and made myself a piece of toast. I set the toaster to three—medium brown.}—Then he tied an onion to his belt Apu: Let’s go to…that line. Marge: But that’s the longest. Apu: Yes, but look: all pathetic single men. Only cash, no chitchat. Marge smiles approvingly as the line moves much faster.”