On the good side, Time Machine is automatic. You basically turn it on and forget it. You get daily backups (incremental) which you can browse, allowing you to restore any file or folder from any previous date. So far, so good.
Now the problems. Backups are done to a disk, with no more level of detail given. There is no way to drill down to individual backups. This causes a problem because it appears the connection between host user data and backup can be easily broken. On three separate occasions now, Time Machine has lost my credentials, and thus my backups. When I reconfigure to continue backing up, Time Machine starts over (assuming I’m a new user), losing my backup history.
Well, the history is not lost, just not accessible. The destination disk continues to show more and more data used, but my backup history is gone. My assumption is Time Machine does some type of session/user connection to the backups, allowing multi-user use of the same destination disk. The critical problem, tho, is that there is no way to chose a specific existing backup to continue using. If your credentials are lost/recreated (which you really don’t control), you get a new session, and thus lose your history.
What is needed is a way to go one level deeper than the disk. The user should be able to chose an existing backup within a disk and authenticated to that backup. I see no way of recovering a lost backup session, only start a new one.
At least I’m able to create manual images of my disk, which I know is reliable, albeit manual.
It’s fairly amazing to me that Time Machine has this flaw, but the history of backup software is horrible, so there is nothing better at the moment.