Average search engine users don’t reformulate queries as we do in IR. They often recycle their query terms, using short queries of 2 to 3 terms. Frequently, their search sessions describe ‘query chains’, and using the default search mode.
Unless they are advanced-searching, most do not use query operators or shortcut search commands. Many do not consult a lookup list, thesaurus, or query logs to expand a query as we do in IR. Most don’t keep expanding a query. After few sessions they simply move on to another Web resource that might satisfy their information requirements.
Most don’t care about searching for very rare terms or terms with a high discriminative power, prefering to search for ‘what is hot’ or for what terms supply their information needs. Period.
Most are lazy users whose mentality is: “Don’t make me think!” or “I’m too busy to deal with a cluttered interface or learn new how-tos”. Many are so lazy or busy that don’t even scroll down a page. Others have a blue-linker mentality; i.e. assuming that blue underlined text has to be a link.
Thus, when a search interface is designed it should take into account the user’s search behavior, shaped mentality, and prejudgments. Their search experience should be guided by intuition and should be obvious, not requiring of extra information in order to search and find relevant documents.
Search engines that do not provide users with a ‘lazy search experience’ often do not attract enough users, visitors, or advertisers. I hope to be wrong about this one, but the two new search engines, Cuil and SearchCloud more likely will not make the A-List, in part because of several usability issues.
Size and hype is not enough.
PS. I forget to mention that:
1. of the two above, Cuil is a bit more user friendly, but its entry page/result page design is awful.
2. “search interface” to me means anything the end-user must interact with in order to search and find. Among other things, this includes the query box, entry page, and the results page.