A recent Jakob Nielsen article states that, “Users often leave Web pages in 10–20 seconds, but pages with a clear value proposition can hold people’s attention for much longer.”
“The average page visit lasts a little less than a minute,” Nielsen states. He summarizes his article by saying that “there are two cases here: bad pages, which get the chop in a few seconds; and good pages, which might be allocated a few minutes.”
Not necessarily. Suppose I’m looking for an installation guide for a water purification system. There are many pages on the way to the page this guide is on. I want to get through these pages as quickly as possible. Ten seconds should be more than enough time to help me find the link I need. These sort of navigational pages should be judged by how accurately and quickly they guide a person.
Even when I get to my page or document on installation, judging success based on how long I spend on the page is fraught with danger. If the content is confusing, I may spend ages trying to understand it and still not complete my task of learning how to install the product.