How old is that flash drive or external Hard drive?
Automated offsite backup available for as low as $5 a month!
When your external finally fails you can dump all your data back down to your new one.

Only have external storage & no offsite backup? Fire / vandalism could effeect you.

Data protection policy 3, 2, 1 says that your important data should have at least
3 copies of your data on at least
2 forms of media with at least
1 offsite for disaster recovery
Example, 1 copy on your pc/mac, usb or NAS, & cloud
If your backup dies or you get robbed, how far back does that put you?