diff --git a/core/modules/comment/migration_templates/d6_comment.yml b/core/modules/comment/migration_templates/d6_comment.yml
index a7ffc9d..f4dff98 100644
--- a/core/modules/comment/migration_templates/d6_comment.yml
+++ b/core/modules/comment/migration_templates/d6_comment.yml
@@ -7,6 +7,8 @@ source:
   constants:
     entity_type: node
 process:
+  # If you are using this file to build a custom migration consider removing
+  # the cid field to allow incremental migrations.
   cid: cid
   pid:
     plugin: migration
diff --git a/core/modules/comment/migration_templates/d7_comment.yml b/core/modules/comment/migration_templates/d7_comment.yml
index 5845999..d4e3c57 100644
--- a/core/modules/comment/migration_templates/d7_comment.yml
+++ b/core/modules/comment/migration_templates/d7_comment.yml
@@ -7,6 +7,8 @@ source:
   constants:
     entity_type: node
 process:
+  # If you are using this file to build a custom migration consider removing
+  # the cid field to allow incremental migrations.
   cid: cid
   pid:
     plugin: migration