Software is meant to change. Customers have the right to change their minds, substitute functionality, and re-order priorities without paying exorbitant costs. Agile assumes change and designs both the product and the process to make change economically reasonable.
What “reasonable, not exorbitant” means:
- Change isn’t free; it should be cheap enough to make good business sense.
- Costs are kept low by technical excellence and small-batch planning, not by refusing change.