IanTurner - 12:13 pm on Sep 3, 2012 (gmt 0)
@Andem, you see that is the real issue with using certain user metrics - different classes of site require different user metrics and have different definitions of success.
I even have some concerns about using length of time on site for informational sites. For instance if you provide a lookup table of html character codes - success could be defined as delivering the code someone wants as fast as possible as in most cases that is what your user wants. In that situation increasing length of time on site is not necessarily a good thing.