BBC reports on Jakob Nielsen's annual report into web usage:
"Instead of dawdling on websites many users want simply to reach a site quickly, complete a task and leave. Most ignore efforts to make them linger and are suspicious of promotions designed to hold their attention.
Instead, many are "hot potato" driven and just want to get a specific task completed.
"The designs have become better but also users have become accustomed to that interactive environment," Dr Nielsen told BBC News.
Now, when people go online they know what they want and how to do it, he said.
"Web users have always been ruthless and now are even more so," said Dr Nielsen.
"People want sites to get to the point, they have very little patience," he said.
"I do not think sites appreciate that yet," he added. "They still feel that their site is interesting and special and people will be happy about what they are throwing at them."
Web users were also getting very frustrated with all the extras, such as widgets and applications, being added to sites to make them more friendly.
Such extras are only serving to make pages take longer to load, said Dr Nielsen.
There has also been a big change in the way that people get to the places where they can complete pressing tasks, he said.
In 2004, about 40% of people visited a homepage and then drilled down to where they wanted to go and 60% use a deep link that took them directly to a page or destination inside a site. In 2008, said Dr Nielsen, only 25% of people travel via a homepage. The rest search and get straight there.
"Basically search engines rule the web," he said.
But, he added, this did not mean that the search engines were doing a perfect job.
"When you watch people search we often find that people fail and do not get the results they were looking for," he said.
"In the long run anyone who wants to beat Google just has to make a better search," said Dr Nielsen.