Summarizing patterns are a way to offer shorter and easier versions of the contract or its clauses or sections, covering just the most essential points. They are not a substitute for the full text, but can help support understanding in several situations.
Not every contract reader needs to know every single detail of the contract. For example, a Force Majeure, jurisdiction or remedies clause may have a major impact if a delay occurs or a dispute arises, but not necessarily otherwise. Readers may not need all the details each time they read the document, either. Sometimes just getting the gist of what the contract is about is sufficient.
Sometimes people may not read long and difficult documents at all (e.g., consumers agreeing to online terms, or employees barely looking at the different internal policies their contracts say they must follow). Offering a summarized version increases the odds of them reading and knowing at least the most crucial information.