Why is the success of a cloud recording dependent on my cable box working?

@XfinityAldrik​ Interesting.  Thanks for the answer.

Followup question:  How is it that a recording remains available at home even after it's deleted from the cloud due to reaching the maximum cloud portion of my DVR allotment?  Is it downloaded back to the box at that point?

Great question Dennis25! While you can delete from the cloud storage for recorded programs, the 'hard copy' of the program will remain on the DVR and will follow the DVR deleting process of deleting the oldest program when space is needed unless the rule is set to keep the program for a year. 

@XfinityPaula​ and @XfinityAldrik​ your answers have been clarifying and helpful.  Thanks.  I think this will be the last followup:  If I set a recording on another device via the stream app or website -- instead of on the box-connected TV -- would that recording still be affected by an outage or other interruption  that affects the box?  My hunch is that the answer will be "yes" as a result of automatic syncing, but I wanted to check in case I'm wrong.

Thank you for your feedback. Yes, Dennis25. If your address is impacted by a reported service interruption, it will mean the scheduled recording will not record the program, regardless of which device or avenue you use to make the recording.