When you have many roles in IAM it too hard to define by name what the role is for Please add description to [monitoring role](https://github.com/terraform-aws-modules/terraform-aws-rds/blob/66336d9c489c4e318799219a7ec5584efdae70be/modules/db_instance/main.tf#L199) aws_iam_role [description argument](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/iam_role#description)