The “presence sensor” options In smartthings, regardless of the actual device type, are all “boundary event“ notifications. That is, there is an event when you cross the boundary, either coming or going. But nothing going on once you are past that moment.
Most people use a presence sensor to change the location.mode on their account, typically from “away” to “home” or from “home” to “away”. This is different then the security. mode which is used for the security system status. Location.mode Is generally just used to indicate if anyone is home.
Then when you create your automations, you indicate what location.mode you want them to be run in.
The following FAQ will explain more about how people use mode. Although the title says it’s for the classic app, the location.modes work the same way in both apps and the examples are all still good.