When you get to the end of an EZ conveyor and it's feeding something that isn't an EZ conveyor, that last zone has to be able to talk to the PLC. The PLC needs to tell it to hold, and it needs to know when a package is sitting there waiting. Map those points during design, on paper, before the panel gets built. Every end-of-conveyor zone. Every zone that needs a commanded hold. Every zone that hands off to a piece of equipment that doesn't speak the same language. Miss one and you find it at commissioning, and now you're modifying a panel at the worst possible time to be modifying anything. It's a small component with an outsized impact, and it's the easiest thing in the whole system to look right past.