In fact, you should not rely on the cloud at all. But if you do and you don’t have good backups that are not cloud-based, consider that data already lost. It’s gone already in the future timeline. That I can guarantee.
So if you want to lose all your data, here’s how you do it: put it in the cloud and wait a bit. It’ll be deleted, disappeared or destroyed soon enough. And that is something you can depend on.