What is a common mistake that people make when writing summaries?

A common mistake that people often make when writing summaries is focusing on irrelevant information. Summaries should capture the main points and important details of a source, but it's easy to get sidetracked by interesting or supporting information that may not be essential to the overall understanding of the content. To avoid this mistake, it's important to identify and prioritize the key points and discard or summarize any secondary information or tangents that deviate from the central message of the source. By maintaining a clear focus on the main ideas, summaries become more concise, accurate, and fulfill their purpose of providing a brief overview of the original content.