I have a Mac SE, and earlier this week dug it out to check if it worked, it hasn't been used since the early 90s. I booted it up from a hard disk with System 7, and of course after using it a bit, it crashed when running MacWrite right into Macsbug, due to some random inter-program conflict .
Yes, even back in the age of the Mac SE, computing sucked sometimes. Floppies died, hard disks went south, crappily written extensions to support various computer extras like scanners were buggy and would bring the system with just a dialog that basically said "oops, you are screwed. [Restart] or [Resume]", and unless you had a debugger installed, the resume button would be dimmed and unavailable. Of course, even though you can see the work you were working on, once that dialog popped up, your work was forever lost unless you had a policy of manually hitting Command-S every time you paused for a break.
If Office or an app like that crashes these days, you can recover data from a temp file, most likely... or it autosaved a version 10 minutes old. However, back then, the only thing saving your work was your manual saves and "Save As..." to backup floppies.
Computers suck in any age. It happens to us all, and nobody is immune. Its an unfortunate fact of life. Best thing to do is keep good backups , and keep your antivirus software updated.
: When System 7 was introduced and before OS X, Mac's operating system was known for crashing on a dime, and leaving change. I remember that on people who were on MacOS 8 and 9 having to hardware reset their machines every 1-2 hours just due to badly programmed apps or extensions. Before Mac OS 7.5, the Macintosh operating system was just called "System".
: For good backups, I'd at least recommend something like Retrospect and an external hard disk, as well as either an online backup system like Mozy for document backups, or periodically burning files to DVD.