I’ve always been a fan of Udi Manber, late of Yahoo and Amazon, now at Google. Popular Mechanics has an interview up with him. From it:
I’ve noticed, anecdotally, when watching people search, that they will rephrase their query over and over again until they get a proper answer. To what extent can that be fixed on the search engine side?
Many ways. First, we take that into account. The results we show you are based not only on what we know of the Web, but also what other people have searched for. Second, we are developing more tools to allow you to refine your queries—at the bottom of many pages, you’ll see query refinements. These are suggestions from us about what your next query should be. And we put it at the bottom because that’s where you run into problems—you tried to read the page, you didn’t find what you want, you may need other suggestions. Plus, we’re working on many other ways to help you with this process. [Search] is clearly a process.