When building video chat functionality, teams must decide whether to build it from scratch, use a low-level API, or opt for a full-featured API that provides more features and prebuilt UI. An API allows developers to add features and functionality to their product without having to build everything from scratch, saving time and money. The choice between a low-level and full-featured API depends on the team's level of control and expertise needed, with full-featured APIs offering a "prefab" approach that requires less development work and testing. The right API can greatly impact the speed and quality of the video chat experience, making it essential to choose one that meets the specific needs of the product and roadmap.