A cloud-based application is often divided into several small services that work together to process a business transaction end-to-end. Even a single operation (within a transaction) can result in multiple point-to-point calls among all services. Ideally, those services should be loosely coupled. It's challenging to design a workflow that's distributed, efficient, and scalable because it often involves complex interservice communication.
https://learn.microsoft.com/en-us/azure/architecture/patterns/choreography
