One of the major problem with working in a project which has hundreds of Microservices as debugging is really hard. It’s hard to find the cause why a request failed because logs are scattered.

You may see user authentication errors thinking that something wrong with user credential but it because of timeout on service which does that, you will only come to know the true reason by looking at logs of multiple services.

As per this principle. Microservices should have robust monitoring and logging mechanisms in place to help diagnose issues and track performance.

For example, each microservice could log information about its performance and usage, which could be used to identify and diagnose issues. This will help you surely you in long run and day to day support work. 

https://medium.com/javarevisited/10-microservices-design-principles-every-developer-should-know-44f2f69e960f