diff --git a/core/modules/datetime/tests/src/Functional/DateTimeFieldTest.php b/core/modules/datetime/tests/src/Functional/DateTimeFieldTest.php
index 3df2582e3e..7ff5f4ee60 100644
--- a/core/modules/datetime/tests/src/Functional/DateTimeFieldTest.php
+++ b/core/modules/datetime/tests/src/Functional/DateTimeFieldTest.php
@@ -850,7 +850,6 @@ public function testDateStorageSettings() {
     $this->drupalGet('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name . '/storage');
     $result = $this->xpath("//*[@id='edit-settings-datetime-type' and contains(@disabled, 'disabled')]");
     $this->assertEqual(count($result), 1, "Changing datetime setting is disabled.");
-    $this->assertText('There is data for this field in the database. The field settings can no longer be changed.');
   }
 
 }
diff --git a/core/modules/datetime_range/tests/src/Functional/DateRangeFieldTest.php b/core/modules/datetime_range/tests/src/Functional/DateRangeFieldTest.php
index e7f0fbbd47..14c4c5aee8 100644
--- a/core/modules/datetime_range/tests/src/Functional/DateRangeFieldTest.php
+++ b/core/modules/datetime_range/tests/src/Functional/DateRangeFieldTest.php
@@ -1356,7 +1356,6 @@ public function testDateStorageSettings() {
     $this->drupalGet('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name . '/storage');
     $result = $this->xpath("//*[@id='edit-settings-datetime-type' and contains(@disabled, 'disabled')]");
     $this->assertEqual(count($result), 1, "Changing datetime setting is disabled.");
-    $this->assertText('There is data for this field in the database. The field settings can no longer be changed.');
   }
 
 }
diff --git a/core/modules/field_ui/src/Form/FieldStorageConfigEditForm.php b/core/modules/field_ui/src/Form/FieldStorageConfigEditForm.php
index 49a45e1cd9..c8b64f59d7 100644
--- a/core/modules/field_ui/src/Form/FieldStorageConfigEditForm.php
+++ b/core/modules/field_ui/src/Form/FieldStorageConfigEditForm.php
@@ -62,13 +62,7 @@ public function form(array $form, FormStateInterface $form_state) {
 
     $field_label = $form_state->get('field_config')->label();
     $form['#title'] = $field_label;
-    $form['#prefix'] = '<p>' . $this->t('These settings apply to the %field field everywhere it is used. These settings impact the way that data is stored in the database and cannot be changed once data has been created.', ['%field' => $field_label]) . '</p>';
-
-    // See if data already exists for this field.
-    // If so, prevent changes to the field settings.
-    if ($this->entity->hasData()) {
-      $form['#prefix'] = '<div class="messages messages--error">' . $this->t('There is data for this field in the database. The field settings can no longer be changed.') . '</div>' . $form['#prefix'];
-    }
+    $form['#prefix'] = '<p>' . $this->t('These settings apply to the %field field everywhere it is used. Some also impact the way that data is stored and cannot be changed once data has been created.', ['%field' => $field_label]) . '</p>';
 
     // Add settings provided by the field module. The field module is
     // responsible for not returning settings that cannot be changed if
@@ -126,6 +120,13 @@ protected function getCardinalityForm() {
     else {
       $form['#element_validate'][] = '::validateCardinality';
       $cardinality = $this->entity->getCardinality();
+
+      // See if data already exists for this field.
+      // If so, alert the user to restrictions on changing the cardinality.
+      if ($this->entity->hasData()) {
+        $form['#description'] = $this->t('This field already contains data, so reductions in cardinality that would delete data are not allowed.');
+      }
+
       $form['cardinality'] = [
         '#type' => 'select',
         '#title' => $this->t('Allowed number of values'),