Segment Logic

Segment logic determines how several conditions combine: with AND every condition must hold at once, while with OR satisfying one of them is enough.

The simple rule is that AND narrows and OR widens, but once both appear in one definition it is the grouping and nesting of conditions that decides the outcome, and most tools evaluate a flat list with a fixed precedence that is not necessarily what was intended. The harder ambiguity lies elsewhere: an AND between two event conditions can mean one event carrying both properties, or a user who fired the event once with the first property and again with the second. Those produce very different audiences and the interface wording rarely makes the difference explicit. A segment returning zero users is the usual symptom of getting this wrong.