Final answer:
Using an extract improves performance by reducing the amount of data loaded during use and minimizing the impact on the source system. Extracts also enable offline access to the data, allowing for analyses without an active connection.
Step-by-step explanation:
The best reason for using an extract instead of a live connection is to improve performance. An extract is a snapshot of data that can be processed and analyzed locally, which reduces the amount of data that needs to be loaded and accessed during use. This leads to faster query response times and better overall performance. Additionally, extracts can help in minimizing the impact on the source system by reducing the frequency of queries against the live data, which can be particularly important for systems that are sensitive to high loads or have limited resources. Finally, extracts provide the ability to allow for offline access to data as the data is stored locally and can be used without an active connection to the data source.