From Jacob Nielsen, The Power of Defaults. Primarily, it discusses the fact that users click the first entry in a search engine on average, typically favouring it 42% over other options.

I’m sure I click the top link quite often believing — maybe falsely — that the search engine’s ranking of the first page is worth my time to at least check it out.

Sometimes, it’s obvious. In the searches below, my search was for “best mouse to buy.”

In both instances, the engines provided me enough information to quickly determine that the first options were in fact likely not relevant to my search. Actually in this case, even the first 3 links in Google had no relevance to my search. MSN seems to have better matches at first glance, and I would have strongly considered the second option. (For those who care, the 4th option for Google was a review of a mouse, actually the same Logitech mouse…).

So, back to the original question. Why do users click the first link? Because they don’t know any better! It’s often difficult to quickly rank the relevancy of a set of search results when they are presented like they currently are on Google and MSN (and all of the other clones). It’s challenging to form an effective search still today … you need often think like the author, which can be difficult depending on the subject (especially when needing to use common keywords).

I don’t know what the search engine companies have in the works. My wish list includes: more relevant results; better at a glance understanding of how a result actually matches with my needs (highlighted keywords can often be deceptive); a better way of filtering out the junk after a search (to better narrow the focus); some method for searching for recent content (as part of a filter) without going to the advanced tab; the ability to exclude web sites for some period of time so that I can ignore them; slick user interface (maybe using a more DHTML/XMLHTTP/AJAX style approach rather than page round-trips?) and generally fast (I’m willing to wait a ‘bit’ if the result quality and the search experience is very nice).

Related: MSN Search has a very interesting UI for displaying some of the search criteria and specific settings. Just click “search builder” to try it your self. It did improve the MSN search results for the mouse search. More content related to my sample search was returned at the top.

Jacob’s conclusion: make sure your content ranks high in search results. Like we needed a study for that.