TimeMeasureStart as well as TimeMeasureEnd compose a pair of objects measuring the time the agents spend between them, such as "time in system", "length of stay", etc.
This object remembers the time when an agent goes through. Later on when the agent goes through one of the corresponding TimeMeasureEnd objects, the time the agent spent between these two "marker" objects is measured.
How-To video: Measuring time in system
You must ensure that each agent going through this object later on goes through TimeMeasureEnd object mentioning this one as its pair.
Demonstration model: Measuring Length of Stay