Content can be ready for a brochure yet unsuitable for a searchable catalogue or mobile task. A product name may mean different things to different staff. A spreadsheet may mix current and retired entries. A service description may omit the information a visitor needs to choose between two similar options. These issues matter before visual design because they affect labels, filters, fields and customer expectations.
Choose a small sample that includes an ordinary item, an exception and an item that has changed. Ask the team to explain each without filling gaps from memory. Write down which information is authoritative, which can be published and who may correct it. The aim is a practical starting collection, not a promise to clean every historical record during a website commission. If substantial preparation is required, show it as work with a clear owner and review point.