What do you mean?

1. The file has a number to the left of it, as in multiple sources, or

2. You see the same file name over and over

If #1, that user is simply one of several owners of that copy

If #2, that's pretty weird, although I have downloaded several copies of a certain file just to compare quality. Also, it is possible that someone is sharing both high bitrate and low bitrate files

Hope this helps