Thank you for posting here in the Community. I'm here to help provide additional clarification about the Temp folders from QuickBooks Desktop.
The QBBackupTemp folder will continue to show and won't get deleted automatically for any unsuccessful backup on the program. These type of folders are also safe to be removed manually on your local files.
For more insights into QBBBackup Temp folders, I'm adding the support link on this:
If they're no longer working as designed and the folders aren't deleting on its own, I recommend contacting our QuickBooks support. One of them will be able to review your account and ensure you'll get back on track with your backups.
Here's how you can reach them:
Please keep in touch with me here so I can ensure your issue regarding the backup gets fixed. Cheering you and your business to continued prosperity.