I'm testing Google Analytics' accuracy with my newly built website.
Only about 2 seconds after I visit my website, I see the number of "active users on site" increases (in Google Analytics' real-time reports). So the increase in number is quite accurate.
But when it comes to deducting leaving visitors, I find it quite inaccurate. After I leave my website, the number takes about 5 minutes to decrease.
Is that normal or I missed some steps when installing Google Analytics?