Guest relations are a big part of the job. But wait, there's more. As part of watching Efficiency, you basically do whatever it takes to make things work smoother, faster, better. In a restaurant that means you have to stock up on plates and so forth, maybe more needs to be broken out. Food supplies need to be replenished, prep work done for later today or tomorrow.
Food needs to be stored safely.
Hot foods must be over 160, cold meats should be kept below 40. If you sell something, for example at restaurants or merch locations, hourly readings need to be taken, and sometimes recorded, analyzed, acted upon. Cashiers may need something voided, or additional coins or small bills. The serving line frequently benefits from additional assistance from the Lead in one spot or another. The exact spot, of course, is always changing.