Epic user stories are generally large user stories that are unable to be completed with one single iteration. In order to understand and improve them, they must be broken down into smaller user stories. Instead of being overwhelmed by a daunting task, creating epic user stories allows you to break down the issue or goal you are aiming to complete, and have reasonably attainable action items to works towards. It allows you to create a hierarchy for your backlog of tasks that all fall under the category of achieving one main objective. This way, no steps or ideas are lost in the process, and each one represents a discrete task towards a common goal.
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