The goal of Lean-Agile development is to incrementally deliver working courseware that meets the stakeholder’s needs. This means the increment quality is ready for delivery.
Incremental gratification with each end-of-iteration demo helps theoretically prevent scope creep, but in our experience it simply reduces risk and continually builds trust (when you meet your iteration goals). Scope creep in courseware is an ever-present problem that Lean-Agile does not magically solve.
Delivering a working and tested increment of courseware every two weeks builds trust because the Lean-Agile process plans and tracks the working product increment. The delivery allows stakeholders to see and interact with the instructional content in a partial player that is working and tested, so the user interface works correctly. This direct visibility into the project status every two weeks is straightforward and concrete.
Having a two-week fixed iteration helps shorten the lead time for stakeholders or customers to get that courseware increment into their hands faster.
One week iterations may more easily fit into EVMS because of weekly updates for cost efficiency and schedule efficiency.