There are several motivations towards microservices. However, the one that I want to start with is when we are dividing it into components having single responsibilities, we are abiding by the SRP (Single Responsibility Principle). Single responsibility is actually one of the first five Object Oriented Principles, also known as SOLID (https://en.wikipedia.org/wiki/SOLID_(object-oriented_design) ). This single principle, even if it is at architectural level or low level, it makes things simple and easy. Here, in the case of microservices, separates components from each other. So, the reason for modifying a component will be related to one single functionality. Other components and functionalities of the system will work as they were working before. This is how being separated and being independent as microservices makes them easier to modify without affecting others.
Here are some of the other reasons why it is necessary to separate microservices.
