The main reason to put the date in the file name rather than to rely on the Last Updated or Created By dates are because those dates can be artifically altered. If someone opens a file that has a formula, even if the formulas reference static data and nothing is apparantly altered at all, a "change" has been made. Which means that when Word or Excel prompts you to save changes many people click "yes" out of habit, figuring that there is no big deal because nothing in the file changed. Now, all of a sudden that file is out of sequence.
And, if your office should merge or separate storage drives, all of a sudden all files created before the merge or separation now show the same date.
This one hits home twice:
I once was bashed for using the "European" date format (yymmdd) in my files instead of the American. Also, we have a committee to draft entries in our internal on-line dictionary and the results are not dissimilar to the one in the comic.
Sort-by-date is useless as often people open obsolete documents, accidentally make a minor change and are then prompted to save when closing. You could use version names to get around, but people are often embarrassed by a file name like: simple-one-page-note-v45.docx.
I don't understand why so many people / businesses use the month - day - year or month - year - day naming conventions. If you use a year - month - day naming convention, then alphabetical and chronological order synch up. So, computer files will be in order from oldest to newest.