Searching is one of the top activities for Internet users. It drives profits for the search engines as well as the marketers listed on the search results pages. A site search box on your company web site can increase profitability; yet site search is not all that common.
A new visitor to a web site makes decisions quickly. They are looking to accomplish their goals and satisfy whatever need brought them to the page in the first place. Web sites, where visitors may or may not find what they need within a click or two, risk losing a chance to convert. A web site that is not optimized for search engines probably isn't going to be useful to your visitors either.