A majority of US Internet users regularly experience search engine fatigue, according to a Kelton Research study commissioned by AutoByTel.

Search fatigue was defined as impatience or frustration at not finding the exact relevant information a user looked for right away.

"As people use the Internet at home more and more users get broadband, what was once fast is now slow," said David Hallerman, senior analyst at eMarketer. "This is the nature of computing, not just the Internet and search engines."

This is not a new phenomenon, although it is a persistent one. In July 2006, a DoubleClick-ROI Research study found that about 36% of US adult Internet users would try another search engine if one failed to deliver results.

The percentage of time spent on search decreased from 2003 to 2007, according to the Online Publishers Association.

Since the figure is a percentage, it does not necessarily mean that the actual time spent on search decreased. It does suggest, however, that search engines have become more efficient—and that searchers have gotten better at using them.

Search engine improvement also fuels rising expectations, with users growing used to effective searches. Instead of an indictment of search engines, search fatigue can be viewed as a measure of their success.

Brush up on your search tactics. Please read eMarketer's Search Marketing: Counting Dollars and Clicks report.