docs: enhance modules section

Author: lechnerc77

.wordlist.txt

@@ -65,6 +65,7 @@ PowerShell
 powershell
 README
 readme
+reusable
 runtime
 spf
 SSO

sample-setups/README.md

@@ -31,7 +31,9 @@ The folder `basic-setup/subaccount-setup` contains the setup of subaccounts. For
 
 ## Modules
 
-We have created a set of modules to encapsulate the reusable parts of the setup. You find the modules in the folder modules. Learn about the modules and their usage in their respective `README` files.
+We want to keep our Terraform configuration as simple and concise as possible. To achieve this we encapsulate reusable parts of the setup in [modules](https://developer.hashicorp.com/terraform/language/modules). This allows us to reuse the modules in different setups and to keep the configuration DRY (*Don't repeat yourself*). A benefit of this approach is that we can centrally manage governance topics like naming conventions and labeling strategies for all setups.
+
+You find the modules in the folder "modules". Learn about the modules and their usage in their respective `README` files.
 
 ### Naming Conventions and Labeling