When Illustrator crashed while I was working on an .aic cloud document, I lost a day's worth of work even though the settings are set to auto save every 5 minutes. This has worked before with no problem but this time there was no autosave recovery when restarting and no temp files in %appdata% either.
Granted I was careless and forgot to manually save, however at no point was there any indication from the software that auto save was not functioning. Maybe displaying a warning of some kind when this feature is not working would help.

As a sidenote, when I talked to Adobe support about this issue they simply stated that Adobe recommends only working on files locally, which begs the question why implement a feature which is so unreliable that not even Adobe themselves can recommend using?