Almost every client will tell you that they want a search engine on their site to make it usable, easy-to-use, easy-to-navigate. That is what user interface and information design is for. I used to enjoy telling people that search was the remedy for a bad Web site, and that if site was doing its job no one would use search. I think that is less true today because we have trained people to rely on search more and more.
Search engines are not designed for Web sites. They are designed to be search engines -- connecting people who are not yet at their destination with either the destination they are looking for, or a list or potential destinations that are likely to have what they are looking for. What they are not designed for is way finding at the destination itself.
The typical search engine algorithm does not give weight to what the business wants people to see when they search for a specific term. Most people have no idea how their own search engine ranks search results. And even those that do are unlikely to ensure that search results meet the needs of the business. Yes, the needs of the business should correspond to the needs of the user, but the business has the opportunity and responsibility to affect the search results.
A good analogy is paid vs. organic results. Why not pre-determine the top-three links you want a user to see when they search for a term and then allow for the organic results below? The organic ranking could be based upon page views, a relevancy rank of the language on the page, the posted and/or modified date, or any combination of criteria. Then allow the user to sort the results based upon that criteria. But why not use the opportunity to pick what links you show for key terms, in essence doing your own paid keyword advertising on your site?
Go to your Web site, search for a term, and then consider that is presented to you in the search results. Are those the pages you want people to go to? Can you even tell what pages they are? If the answer is no your organization needs to take a more active role in determining how search results are generated.