Data is data is data. If they lost their emails then they lost data in general - which means their backup plans / systems SUCK. If they lost their quarterly reports do you blame their lack of backup solutions or their HDD which finally failed after 6 years of continuous operation?? Everyone who is anyone in tech knows that backups are *your* responsibility. POP3 data is just another thing that is necessary to back up; if you didn't make a local IMAP repository copy, and the email server at your ISP dies and takes down all your saved emails with it, will you be just as happy as blaming IMAP for not saving those copies??