What’s the difference between a user story and an epic?
How many times did you hear this question: "Is that an epic or a user story?" Is there a simple rule to answer the question?
A few days ago, I read the following sentence in a post from Dan North. The remark in brackets is particularly obvious:
Usually, the business outcomes are too coarse-grained to be used to directly write software (where do you start coding when the outcome is “save 5% of my operating costs”?) so we need to define requirements at some intermediate level in order to get work done.
This gives a perfect example of something that we cannot call a user story. It doesn't matter how we call it (be it an epic, a feature, a capability...) as these terms don't have a well accepted definition. All we need to know is that it is definitively not a user story.
We knew already how to differentiate a user story from a task — ie something that is too small to be a user story. Now that we are able to identify as well something that is too big to be a user story, we have a quite good understanding of the user story, even though it's a negative definition.