I’ve found the expectations of my virtual patrons to be just as high as patrons in the building. This being the case, if they aren’t satisfied with an answer, they tell me so. This is how reference works sometimes.
Their usual instance leads me to believe that when they do stop responding they are satisfied. If I hit the question spot on and give them a webpage that answers their question, I almost more often than not get a ”[user has disconnected]” message after asking them if they like the site.
Some may take this as an insult or a sign of dissatisfaction, but while it might not be the most polite move, I think in many cases it means we’ve done a fine job.