diff -u b/core/modules/auto_updates/src/ReadinessChecker/DiskSpace.php b/core/modules/auto_updates/src/ReadinessChecker/DiskSpace.php
--- b/core/modules/auto_updates/src/ReadinessChecker/DiskSpace.php
+++ b/core/modules/auto_updates/src/ReadinessChecker/DiskSpace.php
@@ -10,7 +10,7 @@
 class DiskSpace extends FileSystemBase {
 
   /**
-   * Minimum disk space (in bytes) is 100mb.
+   * Minimum disk space (in bytes) is 100 MB.
    *
    * @todo Determine how much the minimum should be now that we will be using
    *   Composer in https://www.drupal.org/node/3166416.