In software development and product management, an abuser story is a user story from the point of view of a malicious adversary. Abuser stories are used with agile software development methodologies as the basis for defining the activities that should be actively blocked or mitigated by the software and proven by automated regression testing.
A user story is a concise description of functionality valuable to a user. Once Points are estimated for each, a ballpark budget may be computed.
How to communicate about realistic budgets and a timeframes because success requires clear communication on Estimates, Targets, and Commitments.