One of the problems is that the location the data file is not standardized. It usually (but not always) starts out in:
c:\users\public\documents\intuit\companyfiles
but if the user sends the file to their accountant for quarter-end or year-end work, then they get it back with changes, the place where that new file ends up is completely unpredictable. I've seen folks run it from the email attachments location just because the accountant sent it back to them attached to an email. Most people don't have a good grasp on file organization, so you just can't predict where the thing will end up. I had one recently where the live data file was on a flash drive, plugged into a rear USB port, long forgotten of course.
It's gotten a little better with the new versions that allow you to upload the file to your accountant directly from within the program, and consequently, download their changes to your file directly from within the program. This keep the file where it was in the first place at least. The accountant has to participate in the program for this to work, so it's not universal. A step in the right direction, though.