for f in *.txt; do cat $f; done

Will error for example. It works fine for filenames without space, but if the filename has space in it, it will be interpreted wrong. But if your testing batch doesn’t have spaces in the filename, you won’t see the issue until it’s used on a file that does. Note ‘cat’ is a placeholder, any function/script that can be used on a file here will have the same issue.

Something similar to that caught me last week while I was unzipping multiple mods in bulk for a game.