Update modules/configuring/proc-provisioning-your-custom-configuration.adoc

Author: themr0c

modules/configuring/proc-provisioning-your-custom-configuration.adoc

@@ -20,6 +20,8 @@ It contains one secret per line in `KEY=value` form.
 
 . Author your custom `{my-app-config-file}` file.
 This is the main {product-short} configuration file.
+You need a custom `{my-app-config-file}` file to avoid the {product-short} installer to revert user edits during upgrades.
+When your custom `{my-app-config-file}` file is empty, {product-short} is using default values.
 
 ** To prepare a deployment with the {product} Operator on {ocp-short}, you can start with an empty file.
 Creating a custom file, even an empty one, is required to avoid the {product} Operator to revert user edits during upgrades.