diff --git a/src/Runner.php b/src/Runner.php
index b5afa71d05..607c1271f3 100644
--- a/src/Runner.php
+++ b/src/Runner.php
@@ -425,11 +425,17 @@ private function run()
         // If verbosity is too high, turn off parallelism so the
         // debug output is clean.
         if (PHP_CODESNIFFER_VERBOSITY > 1) {
+            if ($this->config->parallel > 1) {
+                echo "Parallel processing disabled for clearer output at higher verbosity levels.".PHP_EOL;
+            }
             $this->config->parallel = 1;
         }
 
         // If the PCNTL extension isn't installed, we can't fork.
         if (function_exists('pcntl_fork') === false) {
+            if ($this->config->parallel > 1) {
+                echo "Parallel processing requires the 'pcntl' PHP extension. Falling back to single-thread execution.".PHP_EOL;
+            }
             $this->config->parallel = 1;
         }