Best Practices ASP.NET, what's the point of layering?

Question

ASP.NET

I stumbled upon the Solution Arch article
Everything is cool, but without subtleties ...
Why such a layering? Repository => Service
Why is the entire solution on Github split into projects?
Specifically, why are the models in a separate project and the service separate?
Or is it due to different layers of architecture?

Answer 1

A service is a business logic that allows you to abstract from the DAL with its repositories.
Layers:
It is customary to split into projects, as a rule, both for logical separation, as well as the ability to painlessly wrap any such module in a NuGet package and connect it in many places. In the wake of this idea, .NET Core was born.