There are a number of times whenisn't appropriate:
If you want to list many files on the command line, it may be easier to use a carefully constructedexpression.
As we mentioned earlier, filename completion and wildcards don't mix.
If you need to use a wildcard, you can't use filename completion.
For example, you might want to match a filename by the end of its
name; if you have lots of files starting with a but only one
of those filenames ends with .c, it's probably easier to type
a*.c than to use filename completion.
Filename completion is obviously less worthwhile if you have to type most of the filename before you can use it. For example, if you have a lot of files with similar names, filename completion won't help an awful lot. (This may say something about the way you name files - the remedy might be to think up some more distinctive names.)