The short answer? Super friggen safe.
This gets a little technical and is intended for the tech heads out there, but the point is that there are as many copies of your images in as many places to keep things as safe as possible.
I shoot with a camera that records RAW files to one card, and medium resolution JPG files to another. The RAW card is formatted every wedding, but I fit about two months worth of weddings on the second JPG card. (EXTRA COPY 1)
The night I get home, I download images onto my computer (SSD storage) and generate medium resolution smart previews overnight, which are automatically uploaded via dropbox into the cloud (OFFSITE COPY 1)
The SSD is backed up to a Time Machine automatically (EXTRA COPY 3)
Manually once a week I’ll clone my SSD to a Drobo. (EXTRA COPY 4)
Once every few months I’ll archive finished work. I’ll move it from the SSD to the DROBO and an array of JBOD disks. (Two copies of the archived files). And every 6 months or so I’ll copy these archives to a JBOD array offsite.