The line cook(s) that is obligated to pick up the slack of a previous cook in order to have a successfull shift/not stuggle. Or the opening cook that is obligated pick up a closing shift because the closer called out. You can make someone you don't like "the next guy" by purposely doing somthing (or not doing somthing) that you know they are going to have to do when they clock in for the shift. But, you must yell "NEXT!" when performing the act thats going to screw them or its not official.
Cook 1: "We have just enough fry seasoning for the night."
Cook 2: "Perfect, im not opening tomorrow...NEXT!"
The opener is obligated to make fry seasoning because we can't serve unseasoned fries...making him "the next guy".