diff --git a/core/modules/migrate/src/Plugin/Migration.php b/core/modules/migrate/src/Plugin/Migration.php
index 1343d1d5723ca8bfbdf8ed896f86b3c7a52c376e..a03ce579e3d82e55b65cf28ebf519c62eb15610a 100644
--- a/core/modules/migrate/src/Plugin/Migration.php
+++ b/core/modules/migrate/src/Plugin/Migration.php
@@ -384,13 +384,12 @@ public function getSourcePlugin() {
    * {@inheritdoc}
    */
   public function getProcessPlugins(?array $process = NULL) {
-    if (!isset($process)) {
-      $process = $this->getProcess();
-    }
+    $process = isset($process) ? $this->getProcessNormalized($process) : $this->getProcess();
     $index = serialize($process);
     if (!isset($this->processPlugins[$index])) {
       $this->processPlugins[$index] = [];
-      foreach ($this->getProcessNormalized($process) as $property => $configurations) {
+
+      foreach ($process as $property => $configurations) {
         $this->processPlugins[$index][$property] = [];
         foreach ($configurations as $configuration) {
           if (isset($configuration['source'])) {