You can update only the services you want/need, allowing you to spread an update out. Especially for young companies and start-ups, it is widespread to have unclear and changing specifications. As changes and new features come in, you can gradually update your backend. For a lot of cases, adding features is equivalent to adding new services.

For example, if you have a social media app and you want to offer the functionality to comment on posts, it would only take you to add a Comment Service. This service would do nothing else but record comments on content.

If you are then tasked later on to add an "Answer" feature to your app, it could be an extension of the Comment Service. This feature could also alternatively be its own new service. Either way, adding these features can be done without touching the other parts of your backend at all! 

To conclude, microservices allow for gradual functional extensions. Finally, let's explore common microservice use cases.