The entire goal of the work processes is to deliver value. "Working software is the primary measure of progress." - Agile Principle #7 1 Once the team has completed work (per the Definition of Done 2), they show their working software. At the team level, this is the Iteration Review 3. At the Program Level, this is the System Demo 4.Iteration Review
System Demo
References
1 - The Agile Manifesto - Principles Behind the Agile Manifesto https://agilemanifesto.org/principles.html
2 - Social Contracts - Definition of Done https://qnetconfluence.cms.gov/display/LACE/Definition+of+Done
3 - Scrum Guide - Sprint Review https://scrumguides.org/scrum-guide.html#sprint-review
4 - Scaled Agile Framework - System Demo https://www.scaledagileframework.com/system-demo/