diff -u b/core/modules/field_ui/src/Access/FormModeAccessCheck.php b/core/modules/field_ui/src/Access/FormModeAccessCheck.php
--- b/core/modules/field_ui/src/Access/FormModeAccessCheck.php
+++ b/core/modules/field_ui/src/Access/FormModeAccessCheck.php
@@ -83,7 +83,7 @@
 
       if ($visibility) {
         $permission = $route->getRequirement('_field_ui_form_mode_access');
-        $access->orIf(AccessResult::allowedIfHasPermission($account, $permission));
+        $access = $access->orIf(AccessResult::allowedIfHasPermission($account, $permission));
       }
     }
     return $access;
diff -u b/core/modules/field_ui/src/Access/ViewModeAccessCheck.php b/core/modules/field_ui/src/Access/ViewModeAccessCheck.php
--- b/core/modules/field_ui/src/Access/ViewModeAccessCheck.php
+++ b/core/modules/field_ui/src/Access/ViewModeAccessCheck.php
@@ -83,10 +83,10 @@
 
       if ($visibility) {
         $permission = $route->getRequirement('_field_ui_view_mode_access');
-        $access->orIf(AccessResult::allowedIfHasPermission($account, $permission));
+        $access = $access->orIf(AccessResult::allowedIfHasPermission($account, $permission));
       }
-      return $access;
     }
+    return $access;
   }
 
 }