Document when to use service providers

src/guide/concept/configuration.md

@@ -141,10 +141,24 @@ For convenience, there is a naming convention for custom string keys:
 
 ### Service providers
 
-As an alternative to registering dependencies directly, you can use service providers. Basically, these are classes that
-given parameters are configuring and registering services within the container. Similar to three dependency configuration
-files described, there are three configs for specifying service providers: `providers-console.php` for console
-commands, `providers-web.php` for web application and `providers.php` for both:
+As an alternative to registering dependencies directly, you can use service providers. A service provider is a class
+that receives configured options and registers services within the container.
+
+Similar to container configuration files, there are three configs for specifying service providers:
+`providers-console.php` for console commands, `providers-web.php` for web application and `providers.php` for both.
+
+Prefer direct container configuration for application services with a simple definition: a class name, an interface
+implementation, constructor arguments from `$params`, or a closure that creates a single service.
+
+Use a service provider when the registration itself is a unit of code:
+
+- A package registers several related services, aliases, or decorators.
+- A service registration also needs supporting definitions.
+- The same registration should be reused in several applications.
+- Registration depends on runtime checks, optional classes, or environment-specific decisions.
+
+Use a factory class when construction logic belongs to one service. A factory returns an object. A service provider
+registers definitions in the container.
 
 ```php
 /* @var array $params */