SUMMARY
When creating a new backup plan I give it a Description, select the External Storage Device and leave default name for the "Folder on Destination Drive", namely "Backups".  I click "Apply" and answer yes  to run the backup, but nothing happens, and there's no indication why.

STEPS TO REPRODUCE
1. Create a new backup plan
2. Leave the default name for "Folder on Destination Drive" (but ensure a folder of that name does not yet exist)
3. Try to run the backup plan

OBSERVED RESULT
The new plan is created, and it offers to run the backup but when I say "Yes", nothing happens, and there's no indication why.

EXPECTED RESULT
Either: 
1. The new plan runs and creates the destination folder if it doesn't exist
2. The user is informed that the plan cannot run because the destination folder does not exist

SOFTWARE/OS VERSIONS
Operating System: KDE neon 5.27
KDE Plasma Version: 5.27.4
KDE Frameworks Version: 5.104.0
Qt Version: 5.15.8
Memory: 7.7 GiB of RAM