The big challenge for any retailer is to make sure that the people coming into the store actually buy stuff, and research suggests that not scrimping on payroll is crucial. In a study published at the Wharton School, Marshall Fisher, Jayanth Krishnan, and Serguei Netessine looked at detailed sales data from a retailer with more than five hundred stores, and found that every dollar in additional payroll led to somewhere between four and twenty-eight dollars in new sales. Stores that were understaffed to begin with benefitted more, stores that were close to fully staffed benefitted less, but, in all cases, spending more on workers led to higher sales. A study last year of a big apparel chain found that increasing the number of people working in stores led to a significant increase in sales at those stores.

A ringing bell instead of an intercom signals that more help is needed at the registers. Registers don’t have conveyor belts or scales, and perishables are sold by unit instead of weight, speeding up checkout. Crew members aren’t told the margins on products, so placement decisions are made based not on profits but on what’s best for the shopper. Every employee works all aspects of the store, and if you ask where the roasted chestnuts are he’ll walk you over instead of just saying “aisle five.” Want to know what they taste like? He can probably tell you, and he might even open the bag on the spot for you to try.