My scheduled backup did not run. Why?

Work through this list

1. Another backup is running. Only one backup runs per server at a time. A second job waits and is tried again every 2 minutes. There is no fixed time limit, so one long first backup can hold the slot for hours while other jobs wait. Look at Backup jobs for a job in Running status.
2. The server just rebooted. After a reboot, scheduled backups wait 30 minutes. Manual runs do not wait.
3. Backups are paused after a rebuild. A server rebuilt with bw-dr-restore pauses every job. Every page shows "Backups are paused until you resume them." Choose Resume backups on the banner after restoring the accounts. See Rebuild a server from a DR bundle.
4. The job or destination is disabled. A job shows Disabled; a destination can be turned off (deleting a destination only turns it off). Re-enable it.
5. The job has no schedule. A job with no schedule runs only when you start it.
6. The schedule's time has not come. A new schedule first runs at its next occurrence. A missed run does not stack up: an overdue schedule runs once, at its next normal time. An hourly schedule runs one hour after the last run started, so the minute drifts. Times are server-local; around a daylight-saving change a run can be an hour early or late.
7. The licence. With enforcement on and the licence Unlicensed, scheduled and manual backups do not run. A banner shows. In the beta, enforcement is off and the log shows licensing.would_refuse. See What happens if your licence lapses.
8. A service is down or the queue is unavailable. Check systemctl list-units 'backupwall*'. While backupwall-redis is down, Run now shows a failed row. See The console will not open or a service is down.
9. An upgrade or restart interrupted the run. The point is marked failed ("Interrupted ..."). The next scheduled run or Run now takes over.
10. A run went quiet. A run that reads or writes nothing for 2 hours is stopped and retried, up to three times.
11. The account is not in scope. Check the job's Accounts setting: Selected accounts or All accounts except… may leave it out.