WordPress runs its background jobs (emails, backups, order syncs, cleanups) through WP-Cron, which only fires when someone visits. Quiet sites run tasks late or not at all; busy sites run them on top of each other. Cron Monitor shows you every task, how long it takes and when it fails, and lets a real scheduler take over.
Free on WordPress.org. No account, no licence key, no locked features, and nothing sent anywhere unless you set up alerts yourself.
Formerly Cron-Sentry: already using Cron-Sentry? Install Cron Monitor and your settings and history come across automatically.
