We engaged in an assessment & due-diligence of the existing architecture and discovered that the application was designed & developed over long periods to facilitate business requirements & all these were piled into a single monolithic application. The deployment, troubleshooting, scaling, and upgrading of such monstrous software applications was a nightmare.
These are the exact problems that Service Oriented Architecture (SOA) helps to resolve. The foundation of Microservices Architecture (MSA) is about developing a single application as a suite of small and independent services that run in their own processes and are developed & deployed independently. The key was to clearly create the domain map, identify the required business functionality and deploy each of them to be implemented as fully independent, fine-grained, and self-contained (micro)services.