I have a Custom Report looking at a subset of visitors over one a one week period. Specifically, the report is looking for users who match a custom dimension value.
Over a previous 7 day period, the above custom report shows 824,512 visitors. If I apply a “device type is not desktop” segment, I get 389,133. If I then apply a “device type is desktop” segment, I get 140,355.
Where did the other 295,024 people go?
To state the obvious, there are no other filter elements in the segments. The two are inverse of each other, and that’s it. All the reports are on a cron.
I switched to Matomo because the high sampling rate with Google Analytics made analysis flawed. But I’m concerned by the large gap in this case, and am hoping I’m just overlooking something silly.