Early versions of FrameMaker kept all resource files (internationalized strings, dialog box layouts, etc.) in the two subdirectories .../FrameMaker/Resources/{Unix,Core} (the first one for the Unix platform-specific resources, and the second for the cross-platform ones also used by the Mac and Windows ports). We had hundreds of happy customers, and had been shipping for 4 years or more.
But one new customer was calling in a panic. They'd installed the product, and it would work fine, but the next morning, it wouldn't even start up, and they had to re-install it. And then it would break again over night. After much pulling of hair and gnashing of teeth, it turns out that due to some other flakey product they were running, they had previously instituted a nightly cron job that ran around removing any core files it could find (since they were large and wasteful of precious disk space back in the day). And the knucklehead who wrote the script had it do a case-insensitive match on "core" and had it essentially do a "rm -rf" even though no true core file could be a directory. So, every night, our Core resource directory was blown away.
We actually had to change the product, as this was a big, important customer, and they outright refused to fix their cron script. Never had this problem on the Windows and Mac ports.