As mentioned in the first part, a corrupt or incompatible iCloud backup can also lead to backup failure. So, you can remove the corrupt or incompatible backups to see whether it matters. The steps to delete the corrupt and incompatible backups is very easy: heading toSettings > iCloud > ...
Generally, you are able to share an iCloud+ subscription with your family members usingiCloud Family Sharing, which is up to 5 members. That is to say, you can share iCloud storage and its features with your family members, including 50GB, 200GB, or 2TB of iCloud storage and features ...
As collaborative working using the cloud becomes more commonplace, the use of different incompatible cloud providers will be a major headache. Apple is already taking steps to overcome this, with the files app for iOS allowing you to link with any third-party storage you may be using as well...