How can I tell whether WP-Cron is actually running when WordPress posts keep missing their schedule?

WP-Cron is probably not being triggered reliably. It checks for overdue jobs when WordPress runs, so a quiet site can leave scheduled posts waiting. If you have WP-CLI, start with `wp cron event list` and find the post-related hook; a next run time in the past is a useful clue. Then try `wp cron event run --due-now` once. If that clears the backlog, the scheduled task itself is likely fine and the trigger is the problem. Check `wp-config.php` for `DISABLE_WP_CRON`; if it is enabled, your host scheduler needs to call `wp-cron.php` or a WP-CLI cron command on a schedule. Don't leave both a server cron and normal WP-Cron fighting each other. If events still fail when run manually, check the PHP/error logs and any security or cache rule that could block WordPress's loopback request to `wp-cron.php`—that points more toward a plugin or callback error than missed scheduling.