In practice, the auto backup to Samsung Cloud can happen daily, but only under oddly specific conditions, all of which have to be met.
Months can go by without your Galaxy Watch and connected smartphone meeting those conditions. But if your smartwatch hasn't been backed up to Samsung Cloud in ages, you may receive a popup message inside the Galaxy Wearable app that explains how everything works.
In short, your Galaxy Watch backup will be saved to Samsung Cloud once a day if all the following conditions are met:
- The Samsung Cloud backup happens automatically once a day between 1 AM and 5 AM.
- Your synced phone has to be connected to Wi-Fi.
- The connected phone's battery has to be at least 30%.
- Your phone has to be charging.
- The phone's screen has to be turned off.
Needless to say, meeting all these conditions by chance can be a rare occurrence. This explains why your Galaxy Watch may have been backed up to your phone but hasn't been backed up to Samsung Cloud in weeks or even months.
Since there is no (safe) or official way to perform a Galaxy Watch Samsung Cloud backup manually, the next best thing you can do is to try to meet all these conditions.
It really seems like an odd set of parameters, particularly given the narrow night-time window Samsung has set, but there you have it.
