QDF, meaning Query Deserves Freshness, is the principle by which a search engine favours new content over older content for certain topics, even when the older content is more authoritative. It is triggered by a sudden surge in interest, recurring seasonality, or a topic that changes by its very nature – legislation, prices, tool versions, call deadlines. Recognising such a topic is simple: if the results feature articles from the last few days and the titles contain a year, freshness is what decides there. For these topics, it is worth having a single page that you update and date regularly, instead of a series of new articles competing with one another. For stable topics, the opposite holds true, and rewriting the date without changing the content will not help. In generative search, freshness carries similar weight, since models explicitly look for updated information.
See also: Content freshness signal, Information gain, Grounding.
