Okay although rare I have been bitten by this again for the third time over the years.

On older sites that have accumulated thousands of attachments.
Depending on the server you run into issues with backups and restore if the site crashes or if migrating to a new host trying to restore the folder.

Meaning when you have 10,000+ to 30,000 files in one folder sometimes the host will not backup correctly or ftp clients like filezilla causes issues trying to restore or move. Causing loosing files.

In future releases I would suggest to have the attachments be stored in multiple folders.

Such as Sirdude's picupload mod even though it is not suggested to use any more due to security issues he had a great idea for this.

Where it saves attachments in separate folders named such as month and year so they are segregated and broken down into smaller folders.
Example would be something like

All you did was name the root attachment folder for attachments and the script created sub folders under that path as new attachments were uploaded by mm/yy.

Blue Man Group
There is no such thing as stupid questions. Just stupid answers