I found the following strange behavior. I have the event213 that, in February 2020, counts up to 1,228.
Then I made a segment (at a Visitor level) keeping only those visitors who fired event213 at least once. If I check Unique Visitors metric over that segment, i find a number higher than the pure count of event213. How can it be possibile?
Below, a screenshot of February 2020 data:
where "[AC] Utilizzo del Calendario" is event213 and "Clienti Utilizzatori del Calendario" is the name of the segment. The segment is simply built as it follows:
This is not logical to me.
Could someone explain me this phenomenon? Is it an error?