Sometimes content needs to be adjusted for the web, or a rebranding is required, so a content strategy helps to guide clients on what content is needed.
A content strategy can really help with large organizations that have multiple departments and complex websites. I usually work with the project manager to find a way to gather, track and organize content, as well as provide training to create content for the web and within the constraints of the website and/or organizational brand. Even a short descriptive strategy can help smaller organizations to work on content while I continue onto design.