diff --git a/README.md b/README.md
index ee196e534..06e630b41 100644
--- a/README.md
+++ b/README.md
@@ -111,7 +111,7 @@ Read more about how to install the example webhook [here](deploy/kubernetes/webh
 
 * `--kubeconfig <path>`: Path to Kubernetes client configuration that the webhook uses to connect to Kubernetes API server. When omitted, default token provided by Kubernetes will be used. This option is useful only when the snapshot controller does not run as a Kubernetes pod, e.g. for debugging.
 
-* `--prevent-volume-mode-conversion`: Boolean that prevents an unauthorised user from modifying the volume mode when creating a PVC from an existing VolumeSnapshot. Only present as an alpha feature in `v6.0.0` and above. 
+* `--prevent-volume-mode-conversion`: Boolean that prevents an unauthorised user from modifying the volume mode when creating a PVC from an existing VolumeSnapshot. Only present as an alpha feature in `v6.0.0` and above. Defaults to true.
 
 #### Validating Webhook Validations
 
@@ -178,7 +178,7 @@ Other than this, the NODE_NAME environment variable must be set where the CSI sn
 
 * `--enable-distributed-snapshotting` : Enables each node to handle snapshots for the volumes local to that node. Off by default. It should be set to true only if `--node-deployment` parameter for the csi external snapshotter sidecar is set to true. See https://github.com/kubernetes-csi/external-snapshotter/blob/master/README.md#distributed-snapshotting for details.
 
-* `--prevent-volume-mode-conversion`: Boolean that prevents an unauthorised user from modifying the volume mode when creating a PVC from an existing VolumeSnapshot. Only present as an alpha feature in `v6.0.0` and above.
+* `--prevent-volume-mode-conversion`: Boolean that prevents an unauthorised user from modifying the volume mode when creating a PVC from an existing VolumeSnapshot. Only present as an alpha feature in `v6.0.0` and above. Defaults to true.
 
 #### Other recognized arguments
 * `--kubeconfig <path>`: Path to Kubernetes client configuration that the snapshot controller uses to connect to Kubernetes API server. When omitted, default token provided by Kubernetes will be used. This option is useful only when the snapshot controller does not run as a Kubernetes pod, e.g. for debugging.
diff --git a/cmd/snapshot-controller/main.go b/cmd/snapshot-controller/main.go
index 3a8c53000..d3333b820 100644
--- a/cmd/snapshot-controller/main.go
+++ b/cmd/snapshot-controller/main.go
@@ -71,7 +71,7 @@ var (
 	retryIntervalStart            = flag.Duration("retry-interval-start", time.Second, "Initial retry interval of failed volume snapshot creation or deletion. It doubles with each failure, up to retry-interval-max. Default is 1 second.")
 	retryIntervalMax              = flag.Duration("retry-interval-max", 5*time.Minute, "Maximum retry interval of failed volume snapshot creation or deletion. Default is 5 minutes.")
 	enableDistributedSnapshotting = flag.Bool("enable-distributed-snapshotting", false, "Enables each node to handle snapshotting for the local volumes created on that node")
-	preventVolumeModeConversion   = flag.Bool("prevent-volume-mode-conversion", false, "Prevents an unauthorised user from modifying the volume mode when creating a PVC from an existing VolumeSnapshot.")
+	preventVolumeModeConversion   = flag.Bool("prevent-volume-mode-conversion", true, "Prevents an unauthorised user from modifying the volume mode when creating a PVC from an existing VolumeSnapshot.")
 	// TODO(xing-yang): Enable enableVolumeGroupSnapshots when the feature is fully implemented
 	// enableVolumeGroupSnapshots    = flag.Bool("enable-volume-group-snapshots", false, "Enables the volume group snapshot feature, allowing the user to create snapshots of groups of volumes.")
 
diff --git a/pkg/validation-webhook/webhook.go b/pkg/validation-webhook/webhook.go
index 09beecfdc..fdfdaacee 100644
--- a/pkg/validation-webhook/webhook.go
+++ b/pkg/validation-webhook/webhook.go
@@ -70,7 +70,7 @@ func init() {
 	// Add optional flag for kubeconfig
 	CmdWebhook.Flags().StringVar(&kubeconfigFile, "kubeconfig", "", "kubeconfig file to use for volumesnapshotclasses")
 	CmdWebhook.Flags().BoolVar(&preventVolumeModeConversion, "prevent-volume-mode-conversion",
-		false, "Prevents an unauthorised user from modifying the volume mode when creating a PVC from an existing VolumeSnapshot.")
+		true, "Prevents an unauthorised user from modifying the volume mode when creating a PVC from an existing VolumeSnapshot.")
 }
 
 // admitv1beta1Func handles a v1beta1 admission