Even at home
Consumers often buy one (1) big disk to stick all the crud on like photos, and then forget that if that dies, it's all gone so that's an issue I tend to fix first when I help someone (not fun with USB 2 connected drives).
In addition, I wish all designery types who place harddisks upright so they can fall over when spinning a combination of extreme diarrhoea and a strong cough for their efforts, and no food for a week other than mashed Wikipedia pages describing what a head crash is. What lies down can no longer fall - stick with that.
I always run two backups. One is a bare metal restore (i.e. I can cold boot from it and use to restore or even work from that disk instead), and one rsyncs important parts of my harddisk to a local USB drive and once a week via SSH to my personal server (which doesn't do anything else like web serving to keep a low attack surface).
Why two? Just because it's no more hassle than one (it happens overnight) and I value my data..