Agile methodologies embrace iterations. Small teams work together with stakeholders to define quick prototypes, proof of concepts, or other visual means to describe the problem to be solved. The team defines the requirements for the iteration, develops the code, and defines and runs integrated test scripts, and the users verify the results.

Verification occurs much earlier in the development process than it would with waterfall, allowing stakeholders to fine-tune requirements while they’re still relatively easy to change.