I noticed in your documentation this section:
How long time visitors spend on your site. It only shows people who visit more than one page. For those who visit one page only we default to 0 seconds.
Wouldn’t it make more sense to completely disregard visitors that can’t be counted because they only visited one page rather than hitting your stats with 0 seconds when they could have either quickly bounced, spent several minutes reading the article or anything in between?
I know Google Analytics does the same but it makes the visit duration stat rather useless if you get hit with 0 seconds every time you can’t properly track it. It seems the bounce rate is a better stat to track that and it should be disregarded completely in time on site - or maybe i’m missing something?