Why client file sharing goes wrong
Most client files are sent as attachments because it is the path of least resistance. The result is a copy in your sent folder, a copy in their inbox, copies in both backups, and forwarded copies nobody tracks. Portals fix some of this and create a login the client has to remember. A one-time link is lighter: no account on the client's side, nothing retained after the download, and a link you can revoke from your dashboard if it went to the wrong person.