I don't send many faxes, but I need to be able to review them at a later date. I have faxes from 3 months ago that I need to confirm what was sent because it apparently wasn't received. I can see in the call log that I sent something to a fax, but cannot retrieve what was actually sent.
There are Account and Data Retention for Faxes, Voicemails, Call Recordings, etc. After the time frame listed in the article, the information will be automatically deleted. This is why it is good practice to save this information yourself using a tool such as RingCentral Archiver. That way you ensure you have proper backup of all faxes sent.