
An ImpliedRequirement that is a mnemonic for a conversation between developer and customer
This XP core practice collects requirements that have not yet been detailed, in the form of User Stories. This is an ImpliedRequirement that is a mnemonic for a conversation that has occurred between developer and customer. The conversation has progressed to the point where the developer has enough information to write an estimate for the story that can be used in the PlanningGame.
Sizing of User Stories is important. If the story is ‘too large’ the developer will typically underestimate. If the story is too small, the developer will typically overestimate the effort involved. There has been considerable discussion of this and other aspects in the XP literature and forums.