diff -u b/src/Plugin/monitoring/SensorPlugin/UserIntegritySensorPlugin.php b/src/Plugin/monitoring/SensorPlugin/UserIntegritySensorPlugin.php
--- b/src/Plugin/monitoring/SensorPlugin/UserIntegritySensorPlugin.php
+++ b/src/Plugin/monitoring/SensorPlugin/UserIntegritySensorPlugin.php
@@ -38,7 +38,7 @@
    *
    * @var int
    */
-  protected $list_size =500;
+  protected $listSize = 500;
 
   /**
    * {@inheritdoc}
@@ -87,21 +87,24 @@
     $user_register = \Drupal::config('user.settings')->get('register');
 
     // Check if authenticated or anonymous users have restrict access perms.
-    $role_ids = array_intersect($role_ids, ['authenticated', 'anonymous']);
+    $role_ids_after = array_intersect($role_ids, ['authenticated', 'anonymous']);
     $role_labels = [];
-    foreach (Role::loadMultiple($role_ids) as $role) {
-      $role_labels[$role->id()] = $role->label();
-      $sensor_result->addStatusMessage($role->label() . ' has privileged access');
+    foreach (Role::loadMultiple($role_ids_after) as $role) {
+      $role_labels[$role->id()] = $role->label() . 's';
+    }
+
+    if (!empty($role_labels)) {
+      $sensor_result->addStatusMessage('Privileged access for roles @roles', array('@roles' => implode(', ', $role_labels)));
       $sensor_result->setStatus(SensorResultInterface::STATUS_WARNING);
     }
 
     // Further escalate if the restricted access is for anonymous.
-    if (!empty($role_labels['anonymous'])) {
+    if ((in_array('anonymous', $role_ids))) {
       $sensor_result->setStatus(SensorResultInterface::STATUS_CRITICAL);
     }
 
     // Check if self registration is possible.
-    if (!empty($role_labels['authenticated']) && $user_register != USER_REGISTER_ADMINISTRATORS_ONLY) {
+    if ((in_array('authenticated', $role_ids)) && $user_register != USER_REGISTER_ADMINISTRATORS_ONLY) {
       $sensor_result->addStatusMessage('Self registration possible.');
       $sensor_result->setStatus(SensorResultInterface::STATUS_CRITICAL);
     }
@@ -121,9 +124,11 @@
       return [];
     }
 
+    // Loading all users and managing them will kill the system so we limit
+    // them.
     $query = \Drupal::entityQuery('user')
       ->sort('access', 'DESC')
-      ->range(0, $this->list_size);
+      ->range(0, $this->listSize);
 
     // The authenticated role is not persisted and it could have restrict access
     // so we load every user.
@@ -253,7 +258,7 @@
       $row['expected_value'] = ['#markup' => ''];
 
       $row['time'] = ['#markup' => date("Y-m-d H:i:s", $time_stamp)];
-      $row['last_accessed'] = ['#markup' => isset($last_accessed) ? date("Y-m-d H:i:s", $last_accessed) : 0];
+      $row['last_accessed'] = ['#markup' => isset($last_accessed) ? date("Y-m-d H:i:s", $last_accessed) : 'Never'];
       $rows[] = $row;
     }
 
@@ -283,7 +288,7 @@
     // Show query.
     $output['message'] = array(
       '#type' => 'item',
-      '#title' => t('Table shows new and changed users who have privileged access.'),
+      '#title' => t('New and changed users with privileged access.'),
     );
 
     if (count($rows) > 0) {
diff -u b/src/Tests/MonitoringCoreWebTest.php b/src/Tests/MonitoringCoreWebTest.php
--- b/src/Tests/MonitoringCoreWebTest.php
+++ b/src/Tests/MonitoringCoreWebTest.php
@@ -190,31 +190,31 @@
     $this->assertTrue($result->isWarning());
 
     // Count users included admin.
-    $this->assertEqual($result->getMessage(), '3 privileged user(s), Authenticated user has privileged access');
+    $this->assertEqual($result->getMessage(), '3 privileged user(s), Privileged access for roles Authenticated users');
 
     // Add permissions to anonymous user and check the sensor.
     user_role_grant_permissions(RoleInterface::ANONYMOUS_ID, array('administer account settings'));
     $result = $this->runSensor('user_integrity');
-    $this->assertEqual($result->getMessage(), '3 privileged user(s), Anonymous user has privileged access, Authenticated user has privileged access');
+    $this->assertEqual($result->getMessage(), '3 privileged user(s), Privileged access for roles Anonymous users, Authenticated users');
 
     // Authenticated user with privilege of register.
     \Drupal::configFactory()->getEditable('user.settings')->set('register', 'visitors')->save();
     $result = $this->runSensor('user_integrity');
     $this->assertTrue($result->isCritical());
-    $this->assertEqual($result->getMessage(), '3 privileged user(s), Anonymous user has privileged access, Authenticated user has privileged access, Self registration possible.');
+    $this->assertEqual($result->getMessage(), '3 privileged user(s), Privileged access for roles Anonymous users, Authenticated users, Self registration possible.');
 
     // Create an authenticated user and test that the sensor counter increments.
     $test_user_third = $this->drupalCreateUser(array(), 'test_user_3');
     \Drupal::keyValue('monitoring.users')->deleteAll();
     $result = $this->runSensor('user_integrity');
-    $this->assertEqual($result->getMessage(), '4 privileged user(s), Anonymous user has privileged access, Authenticated user has privileged access, Self registration possible.');
+    $this->assertEqual($result->getMessage(), '4 privileged user(s), Privileged access for roles Anonymous users, Authenticated users, Self registration possible.');
 
     $test_user_third->setUsername('changed2');
     $test_user_third->save();
 
     // Check sensor message for user changes.
     $result = $this->runSensor('user_integrity');
-    $this->assertEqual($result->getMessage(), '4 privileged user(s), 1 changed user(s), Anonymous user has privileged access, Authenticated user has privileged access, Self registration possible.');
+    $this->assertEqual($result->getMessage(), '4 privileged user(s), 1 changed user(s), Privileged access for roles Anonymous users, Authenticated users, Self registration possible.');
 
     // Check sensor message with permissions revoked.
     user_role_revoke_permissions(RoleInterface::ANONYMOUS_ID, array('administer account settings'));