According to the PMBOK Guide and the Agile Practice Guide, an iteration plan is a core component of adaptive (Agile) life cycles.
* Agile Life Cycle: In this approach, the project is broken down into small, fixed-time blocks called iterations or sprints. An iteration plan is developed at the beginning of each iteration to determine which high-priority items from the product backlog will be completed during that specific time frame. This allows for rapid feedback and the ability to pivot based on stakeholder needs.
* Predictive (Waterfall) Life Cycle: These cycles rely on a comprehensive, up-front Project Management Plan. The scope, time, and cost are determined early in the project life cycle, and any changes are managed through a formal change control process rather than through iteration planning.
* Product Life Cycle: This refers to the series of phases that represent the evolution of a product, from concept through delivery, growth, maturity, and retirement. It is a broader concept than a project life cycle and does not use iteration plans as a primary management tool.
In the context of PMI standards, Adaptive/Agile environments emphasize " just-in-time " planning. Because the scope is decomposed into a set of requirements and work to be performed (the backlog), the team uses Iteration Planning to commit to a subset of that work, ensuring continuous delivery of value.